Aquarium
by DamonTheGayman
Summary: Eren is a normal boy doing normal boy things, as boys do. His parents have passed, but he still remains in his childhood home next to the beach desperately trying to pull his life together. Little does he know, but he's not entirely human, and neither is the merman pursuing him as his mate.
1. The Eye of the Sea

**Lol hello y'all must honestly hate me at this point I know I'm horrible for not keeping up with other stories. HOWEVER this fic is honestly one of my older ones. I start it like many other fics and add to it once in a blue moon. The fic is currently 11,000 words, so I decided instead of a one-shot to just separate it a bit to make it easier to read. (It is almost done so I will be posting the second and last chapter tomorrow.) This story was based off the song Aquarium by Dark Sarah. Really don't know why but her songs really get my writing spirit a going and the ideas a flowing. So without further ado welcome to my ted talk here ya go.**

**Also, please consider visiting hPKJrwQfk and donating $3 to my broke college ass. Or just look at it to make me feel better lol. Enjoy reading!**

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"It's inevitable Levi. There's nothing you can do. You shouldn't have held this off so long to begin with! Damn, brat." Kenny growled, trying to get his hard-headed nephew to understand that this was the will of the people, not him. _If he didn't procrastinate this long then it wouldn't have been a problem._ The throne room shook with the angry waves of raw magic radiating off the livid prince, coral walls cracking while the guards cowered behind the beautifully sculpted columns circling the throne. Even the local wildlife were nowhere to be seen, cowering away from the angry energy seeping out of the room.

"Like hell it is! There's no_ fucking_ way that I'm fucking shitbrows!" Levi growled, whipping around to glare at said shitbrows huff in distaste at the nickname.

"Who said I would be the bottom?" Erwin began, coming forward but unwilling to stand too close to the fuming prince. "Also I thought I told you to stop calling me that-" Erwin started but was cut off by a _very_ irate prince.

"Shut the _fuck_ up before I shove a fucking pufferfish up your shit infested asshole!" Levi shouted, the water around his form beginning to boil as his anger worsened.

"Levi, be civil!" Kuchel chastised beside her brother, light blue eyes daring her son to backtalk her. Levi glared right back, the water cooling around him as he stared at his mother, his rock in life that always seemed to bring him peace. _Well, most of the time._ He saw the telltale gleam in his mother's eyes, quickly covering his ears and swimming away to evade getting pinched when she lunged forward.

"Get real, Kenny! Everyone in the damn clan knows that Erwin and I can't live with each other! How the hell am I supposed to give my body to this fuck twat when he isn't even _gay!?"_ Levi growled while Erwin nodded in agreement behind him, dark scales twinkling as his tail twitched in an irritated manner. _We need to come up with a decision quickly. Otherwise, Levi will definitely end up killing someone._ Erwin thought before swimming up beside the grumpy sea urchin.

"King Kenny, I mean no disrespect but Levi is right. There's no way I could possibly mate with him. We're just… too different. Can we at least try and find a different way to go about this?" Erwin asked, eyes pleading the king to not saddle him up on a ride he most definitely did not want to go on. Kenny sighed and looked at his loving sister, looking for approval for his other candidate in mind. She didn't like it but nodded anyway, knowing her son definitely would not like it. Kenny hummed and looked toward his nephew.

"You know the story of Princess Karula, right?" He suddenly asked, Erwin shook his head but Levi nodded, remembering that Karula was to be the mother of his betrothed when she produced one. _Before she disappeared that is. Now I will have to mate with this stupid piss hole._

"She was going to bare my betrothed, but then she fled," Levi recalled and the stand in King nodded.

"Correct. The Ackerman clan had… steady relations with the Jaeger clan, so your father and the Chief of the Jaeger clan struck a deal. The firstborn child, you, would marry the royal firstborn of the Jaeger clan. However, plans had changed when she fell in love with a human and she vanished to land. About 2 ultra cycles ago she returned, the moon had called her back to the sea and she could no longer revert back to her human self. She was punished as any mer would be, forced into the ice caves for a few ultra cycles before the leader of each clan took pity on her story. They had viewed this as tragic, noticing how many youths were fleeing to land for a human lover. So… not too long ago, it became legal for someone to bring a human down here to be mated." Kenny said, not flinching at the sudden outburst it pulled from the mermen.

_**"What?!" **_

"When were you going to tell me this?! How the fuck am I gonna run this clan if I don't even know of law changes as important as that!?" Levi growled and Kenny held up a hand to silence him.

"If I recall, you've been resolutely_ ignoring_ me for quite a while now to try and get out of this situation, so how _could_ I tell you?_ Lil' shit.."_ Kenny grumbled to himself and Kuchel took this time to swim forward to continue the explanation.

"Levi, You must have a mate within three days, otherwise you will, albeit reluctantly be forced to mate with Erwin or the next line of choice, which is…" She trailed off and Levi peaked with interest. _I didn't know there was a second person in line for my mate. Surely _anyone_ would be better than fucking douche-brows._

"Who is it?" He asked and Kuchel shook her head and sighed.

"It was not my decision but your uncles, I would just like that to be jelly clear. It's… Hanji Zoe." She murmured and Levi's reaction was instantaneous, faking (or maybe not) a retch before sinking to the sand below them.

"There is no way in Mariana (Mariana trench) that I would ever become mated to that shitty four eyes!" Levi exclaimed and Kuchel nodded, petting his arm gently to try and calm him down._ All these hormones bouncing around inside him need to be released. He should have mated at the last true moon 24 cycles ago! Of course, I couldn't force him to mate then, but the people grow restless. The need to ensure their prince is mated is causing a ruckus among them. Everyone knows if you go too long without a mate you drive yourself to ruin! I don't want that for my baby boy._ Kuchel thought and put a comforting hand on his back, rubbing the smooth area around his dorsal calmly.

"I know, Lee. That is why we give you this chance. Find a willing mate within three days, merman or not, and you will not have to mate with Erwin and or Hanji." She said gently and played with a strand of silky smooth ebony hair behind his ears. Levi nodded and sighed, trying to think of any merman to have ever caught his fancy. _Farlan was hot but… he was obviously in love with a girl already. I don't want to break them apart. I've only met a few humans in my life, the only one cute enough to catch my fancy was a child then… but maybe now the little mer-human is grown._ He wondered, remembering the little boy many ultra cycles ago he had saved from the water, only to find out he was half mer.

**-[Years Before]-**

"Help! H-help! Somebody!" A small voice called, cutting through the water and straight into Levi. He turned his head and swam towards it immediately, concern eating at him as he heard splashing. _Is someone stuck in a net? Shark attack?_ He sped when the sound ceased, fearing the worst as he came up close to the beach, shallow water letting in the light of the sun and nearly blinding Levi. He was still able to see the current dragging its newest victim, a little human boy that Levi could sense was more than just that.

_Is he half mer?_ The signal he was letting out was weak, weaker than any merperson but definitely there, pulsing through the water and straight to Levi's heart. _His heart is slowing._ Quick as a barracuda Levi snapped into action, grabbing the kid and bringing him to the surface, pushing against his stomach as he had seen humans do to one another in the past and sighed in relief when the child began to cough. He held him to his chest and made his way to the dry sand finding a small cove in a nestle of rocks suitable enough for his escape if needed and dry enough for the little mer-human to breathe.

The boy was huffing against the merman's chest, clutching him with his tiny hands as if the merman were to disappear any moment.

"Thank-k you..." The boy murmured, body shivering as he tried not to cry, the panic he had felt wearing off and only leaving fear in its wake. The merman hushed him and pulled him into his lap once he was settled against a rock. The boy nuzzled into him thankfully, letting out a small sigh of relief and hugging the merman tight. After a few minutes, the little boy was calm once more and Levi felt now was a good time to start asking questions.

"How old are you little mer-human?" Levi asked, trying to calm the boy down a little as he saw the fear in his eyes._ Are they leaking water?!_ Eren wiped his tears away quickly and held up 6 fingers.

"My name is Eren! I'm 5 years old!" He answered with a small smile, but let out a tiny screech when a particularly strong wave ended up pooling water into his lap. He clutched Levi tightly and hid his face in the older boy's neck again. Levi hummed and hugged the boy back, hoping the comfort of touch was enough for him. _"Eren…_ Levi. I'm 11. Why are you so afraid?" He asked and grunted when the kid suddenly whipped his head towards the sea, accidentally bumping his head on Levi's chin.

"The ocean wants to eat me! Mommy told me to wait on the beach while she was inside but it told me to go in! It called me! So I did and all of a sudden I couldn't breathe!" Eren rambled and stared at Levi, hoping the older boy would believe him. Levi nodded and watched the waves gently push against the sand, pulling it back into its depths.

"Eat you eh? Maybe it just thought you were so pretty that it wanted you for itself." He murmured and looked into the green eyes of the boy on his lap. _Very pretty. The ocean is greedy and wants everything for itself, that's what my mother told me anyway._

"Really?" He asked, looking towards the water, thighs gently gripping the base of Levi's tail. Levi gave a little whine at that but otherwise said nothing about it. Eren seemed to just realize that the texture against his legs was not the same as his and looked down, eyes widening at the sight of one long what he assumed was a leg. _"Levi_ you only have _one_ leg! Did you lose the other one?! Why is it so big?" Eren suddenly asked looking behind himself to see that it ended it what looked like the fins of a dolphin. He whipped back around and stared at the boy with awe in his emerald eyes. "Are you a fish? That is so cool! Do you know Ariel?" Eren asked in rapid-fire succession, not giving Levi any time to answer the questions before he was staring at Levi's slightly pointed ears. "Wow, you're like an elf too! Do you know Santa?" He asked and grabbed at the pointed end, finding them to be a little slimy.

"Oi, one question at a time brat. This isn't a 'leg' and I'm not a fish. I'm a merman and who is Ariel?" He quickly interrupted, grabbing the child's hands to ensure he didn't jeopardize his sensitive ears. Eren just looked confused before realization and horror dawned on his face.

"YOU DON'T KNOW WHO ARIEL IS?!" He shouted in horror, launching into a very detailed explanation of who Ariel was. "... and she has beautiful long red hair and a green tail. Actually, if you're a mermaid shouldn't you know who she is? She is the princess of the whole ocean and all the mermaids!" He concluded as Levi stared in confusion at the child's explanation. "That's... not possible. No clan rules over the entire ocean and… I've never seen a mermaid with green scales… I don't think it's possible. Besides what makes her so special? I'm the prince of the Ackerman clan, I can do anything she can." Levi said with a cocky smirk, sure that he could whoop this _Ariel's_ tail any day. _Especially to impress such a cute brat._

"Well… she can sing really prettily. She also fell in love with a human." Eren explained, giving a little jump when he felt the reach of the sea tickle his toes. Levi huffed and grinned at the boy. "I can sing better than her I bet. However, I don't know about the human thing. Humans are weird." Levi murmured truthfully, holding back a growl when the brat jumped around his tail. _My tail is sensitive dammit! Be careful!_ Levi wanted to say, but he didn't want to see the boy sad again.

"You can sing? Please sing for me, Levi!" He asked so cutely, eyes wide with excitement and mouth pulled up into an ecstatic smile. Levi couldn't possibly say no to the kid with his face like that. "Fine, then you can tell me who sang better." Eren nodded at this and leaned back, giving the boy some room to sing. Levi took a deep breath and looked at the cute brat, thinking about something that would fit this situation. The lyrics came to him than his voice low as he began to sing.

_"Into the sea, I pull you close to me,_

_Slide 'neath the waves and down into the caves,_

_Please be my love and come rest in my arms,_

_Dream your dreams with me,_

_Slide beneath the sea,_

_Come to me my love to forget the land above,_

_Slide 'neath the waves and down into the caves,_

_Forever with me."_ Levi finished the shanty his mother had sung to his father when they courted, looking at the boy expectantly. Eren was wide-eyed, smiling ear to ear by the time the boy had finished his song.

"Wow! You sound even better than Ariel! Are you a princess too?" He asked, sitting rather still for the song had calmed his weary mind. Even sudden slaps of the ocean waves against his feet and thighs did not scare the young human as he watched the merman. Levi chuckled and smirked, his chest puffing out with pride at the compliment from the mer-human youngster. "No, but I am a prince. Why?" Levi asked, noticing the slight blush starting to take over the boys cheeks.

"Ah, well… it's been my dream to be a mermaid! And and and the internet says that one of the ways to become a mermaid is to marry one! I… I was going to marry Ariel but… uh…" Eren started off in excitement but it quickly became embarrassment the more he spoke. Levi, thankfully, had a wit as sharp as a sea urchins spikes and was able to understand where this was going very quickly. He laughed and brought the boy closer so he could look into his eyes, finding the boys' embarrassment rather cute.

"Hah? I am but a humble prince, uncultured in the ways of mankind, what is this 'marrying' that you speak of?" Levi teasingly asked, having a pretty good idea that it must've been something embarrassing for the boy to blush as he did. _Eren is actually very cute. Like an Axolotl._ Eren fidgeted where he sat and mumbled something before looking up.

"When two people get married… it means they love each other. So… they live together. Forever." Eren explained, picking up Levi's hand where it resided on his thigh. "They give each other a ring for their finger and never take it off. And… they eat together, and sleep in the same bed." Levi nodded in understanding, figuring that this 'marrying' thing is similar to mating.

Have sex, give one another a mating mark, and protect one another until the day they die, then have more sex. A human's 'ring' must be a symbol of their everlasting love for one another, their mating mark. _How odd._ Levi realized that he hadn't been paying attention to the guppy and that he had said something. The boy was blushing hard, his cheeks and down to his shoulders a bright red as he wrung his hands together.

"What'd'ya say brat? I didn't hear you." Levi teased, tilting Eren's head up so that he could look into his eyes. Eren squeaked a bit and mumbled, but after receiving a raised eyebrow from the merman he sputtered out a "will you make my dreams come true and please marry me so I can be a mermaid?" before promptly shoving his face into Levi's shoulder. Levi chuckled, humoring him as he picked up a small clamshell and used some magic to sculpt it into a ring with a shiny pearl at the center.

"Give me your hand brat." He ordered, amused at how quick the kid obeyed him. He placed it gently on the boys middle finger as a good luck charm and gave him a smile. "There. Now we are married." Levi murmured, watching the bright expression on the boys face. He started bouncing up and down, giving this weird squeaking sound that was oddly reminiscent to a dolphin as he stared at it. "I'm gonna be a mermaid!" He screeched right in Levi's ear, the merman giving him a little shove in order to try and quiet him. "Oi! No shouting in my ear dammit!" He growled but it went unnoticed to the brat still staring at the ring.

"Thank you, Levi! I will cherish this forever!" Eren vowed, putting a hand over his heart. Levi nodded and sighed, petting the boy's drying hair for a moment before he heard the unmistakable noise of shouting. He turned to see a woman and a man walking along the shoreline, both long haired brunettes and one had glasses. _Who the fuck-_

"-ren! Eren! Where are you?!" The one called, gathering the attention of the boy on his tail. He stood and waved at them before shouting. "I'm over here mommy!" and then promptly nuzzled back into Levi. Both of the figures turned upon hearing their son and jogged towards them. "Eren! I told you to stay on the sand in front of the…" She began to chastise but stopped upon seeing who her son had met, noting the tail and the tell-tale eyes of an Ackerman. _Oh no._

"Eren! Get away from him now!" She screeched, running forward to grab at her son. Both boys were shocked at the reaction, Levi holding the boy tighter for a moment before looking towards the sea. _Should I take him with me? He can breathe in water right?_ Eren stared up at his mommy, clearly confused at why she was yelling at Levi like that. "Mommy, this is my friend Levi! Please don't yell at him!" As soon as she was within reach she grabbed her beloved child from the merman's arms. Backing up as quickly as possible.

In the flurry of limbs, the clamshell ring fell off and plopped into the sand, the receding waves quick to snatch up the trinket and pulled it into the shallows. Eren cried out, noticing that his precious ring was no longer on his finger and began to scream, hoping it would carry his message across. Levi sure understood it, immediately diving into the shallow pool to search for it. It took a few minutes but he managed to find it unscathed. However, as he had been searching, the boy had been whisked away by the two other humans, and no matter how long Levi waited, he never saw him again.

**-[Back To The Present]-**

_That kid was adorable, and he _is _half merman so there is a chance that he can grow a tail! He was so cute when he asked to marry me, squealing as he did when I told him I would. Maybe he remembers his promise to me? Hopefully he still lives by the same shoreline, otherwise, I'm fucking beached._ With a nod he gave his mother a hug, feeling the smooth dark blue scales melding into dark blue flesh of her back. Despite her age, she never lost her youthful features. While Levi shared many traits with his mother, like her elven nose and grey eyes, he inherited nothing from his uncle or his father. He had the same small stature as his mother and the same silky black hair. His uncle just looked like a little bitch with his long ass face and his gray hair. Said seahorse looking ass bitch glared at Levi from where he was and Levi smirked.

"I think I have the perfect candidate in mind." Levi murmured. He let go of his mother and was gone in a flash of blue scales and bubbles as he hurried to make preparations. Kuchel was about to ask who her grouchy son could possibly want, having shown no interest in any living organism before, but was too late as he suddenly took off._ My little barracuda, where do you go so quickly? I hope that you are able to find a mate swiftly. _She thought, chuckling when she heard her brother cursing her son in low tones underneath his breath. _Will they ever get along?_

Levi didn't think so, finding his way to shore, seeing the moon above the surface. _Remember me, my little Axolotl. I'm comin' for you._

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	2. Down, Down, Down, the Depth of the Ocean

**Hey, so fun fact I have been adding stuff to this right because it wasn't finished and I trusted myself to finish and post it tonight. I went in and added some more plot kinda and actually added an extra 2,000 words, in the middle of the document. So ending has yet to be written. So this means there is a whole 10,000 words without end in sight yet so you guys getting this and tomorrow I will post what I hope (Doubt) will be the last chapter of what is supposed to be a one shot. ugh. Honestly, this really might end up 4 chapters. Smut being next chapter, and an epilogue in the last chapter. IDK yet but for now I'll keep it at 3 definite chapters. Anyway, quick thing is that in this chapter there is a song. it's to the song they are singing which is Aquarium by Dark Sarah (In case you want to play it as you read). Slanted is Eren, bolded is Levi, and both is both of them singing. Anyway, hope you enjoy the chapter!**

**Also, please consider visiting hPKJrwQfk and donating $3 to my broke college ass. Or just look at it to make me feel better lol. Enjoy reading!**

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All his life Eren has lived by the sea, longing to be near it since he could crawl. It was cruel really, despite the fact he lived mere minutes from the majestic waves of the ocean, his mother has never allowed him to venture to close to those inviting waves. Not after he nearly drowned when he was smaller. He didn't remember much from that day, Carla had told him to stay on the beach while she and Grisha went to a neighbor's house to get sunscreen and quickly help them with moving stuff. He tried valiantly to do as his mother asked and stay put and play on the sand, but the ocean called to him so strongly, he merely answered. His memory went blurry after that, a dark figure being all he could recall before he remembered his mother's worried and crying face.

They banned him from going to the beach for nearly 5 years after that.

He loved the ocean so much, aching for it every night as he fell asleep. Eren never understood what his parents had against the sea since he would often catch her staring almost longingly at it through the kitchen window. Or even why they had moved to a house right next to the sea if they hated it so much. Whenever he had asked them why they didn't like the ocean, his mother merely replied with "He is dangerous, the sea will take you from me" before changing the subject altogether. However, he will never know what she meant. Today marks the anniversary of her death for 2 years ago today she drowned, her body disappearing into the ocean without a trace. His father left shortly afterward, half insane with grief before he put a bullet through his skull. He sometimes heard her, when the moon was high and the sea restless, he'd hear her voice among the waves, warning him to stay away.

To this day he still has not stepped foot in the sea, never feeling the time was right. Not to mention he felt a need to obey his parents wishes one last time, even if he didn't understand them.

Tonight was different, however, unbeknownst to our young protagonist.

"The blue moon is tomorrow night... isn't it…" He whispered, staring out the small window of his home and towards the sea.

The white of the moon just peaked passed the water, tantalizing the senses with the light it would soon bring. The sand dunes in his backyard seemed to almost glow in the moonlight, the wave lapping at the shore with loud crashes. The long grass swayed gently in the breeze, hiding the nesting seagulls that are resting for the night instead of bothering the people on the boardwalk. If he listened hard enough he could hear the commotion that was the boardwalk. The rollercoasters rambling down the tracks, the children crying in glee and sadness as they ran up and down the boards. The gulls letting out piercing shrieks as they searched for fallen fries and popcorn. He could remember his parents taking him there in the evenings, walking up and down the boards, eating Kohr Bros. ice cream and playfully eating a bit of both his parents when he 'tricked' them into looking at something else. He had many fond memories there, going with Mikasa and Armin in the summer for a bite to eat to taking his first girlfriend mini golfing.

He was alone now though. His parents were gone leaving him a house he couldn't part with. Mikasa is in Japan with her fiance, becoming a leading businesswoman in multiple corporations. Armin is off in Africa, exploring the coasts in order to study the ecosystem for educational and preservation purposes. Sasha and Connie are becoming world-class chef's traveling all across the US of A. Reiner and Bertolt are training to be professional wrestlers, more so Reiner than Bertolt as Bertolt just does what Reiner wants because he loves him. Historia is in college to become a psychologist for kids, and Ymir followed her to become what no ones knows exactly. Annie was in Japan with Mikasa becoming a judo champion. The only one left in their little corner of the world is Jean, and Eren isn't the type to hang out with horse face fuck twats who can't keep his lips to himself. At one point in time, they had dated. It was a wild and turbulent relationship, but Eren had loved him nonetheless. Big mistake. Two years after they first started dating, Eren went over to his house to surprise him on their anniversary, only to walk in on him and some guy having sex. Eren wasn't about to take that lying down and broke up with him immediately. Eren avoided him like the plague after that, ignoring any attempts at rekindling what was lost. After a few months of grieving and feeling like shit, Eren tried to pull a rebound with a girl named Mina. Things were slowly getting better until he found Jean having sex with Mina in her bedroom. Jean tried blaming the whole thing on her but he soon found out that he threatened to tell Eren if she didn't comply with his needs after they had sex the first time.

Last Eren saw of him he was still working at Manco & Manco Pizza as a busboy and sometimes the head of house. But now Eren had no friends, alone in his own personal aquarium, swimming aimlessly but longing to be in the sea all the same. He couldn't figure out why, but despite this longing to be somewhere else, he felt no desire to leave the area. He felt as if he were to leave then he would miss... something.

He sighed and closed the blinds, debating whether to follow tradition and go to bed early as his mother would have wanted or stay up to do some taxes. He decided to do as his mother would have wanted and gone to bed, closing the blinds in his room before remembering his mother was gone, he no longer needed to follow her superstitions. _Why would the moon make me go into the ocean anyway? It doesn't even make sense! Boarding up the house when a full moon rises to make sure the 'moon doesn't steal you from me'!_ He thought derisively, opening the blinds to let in some eerie moonlight, throwing away her superstitions once and for all.

_Besides, the moon is so beautiful when it's full! It'll be nice to fall asleep to it._ Eren noted and yawned, scratching his head as he walked over to his bed. With a thump, he fell into the dark blue comforter and promptly fell asleep.

[Aquarium]

When he awoke it was to the sound of singing. Light and airy it seemed to dance through his head, pleading for him to stand and listen to it more. Eren blearily opened his ocean blue eyes, immediately drawn to the window glowing from the moonlight. _Why did I wake up…? Dammit, not this again._ Eren yawned and sat up, looking around sleepily to see if anything was off. Eren is a horrible sleeper, often waking up at odd hours in the morning and night for 20 minutes or so before he was able to fall asleep once more.

His room was just as messy as before, shirts and pants were strewn across the back of his chair, his desk covered in papers and random folders that he was supposed to organize last week for the Aquarium. A pizza box still sat on the floor by the door, Eren being too lazy to throw it out from two nights before. He sat up and stretched, looking around to see what had him up before he realized what it was. Iridescent moonlight peeked through his window, beams of light reflecting off every surface, hypnotizing him as he walked right out of his room. His legs had a mind of their own, his brain seemingly empty as he walked out of his house, feet planting themselves in the sand. The voice was louder now, the sweet cadence of it caressing him like a lover.

_It's beautiful… where is it coming from though?_ He wondered, feeling the sand shift beneath him as he walked towards the ocean. That familiar ache still resided deep in his chest, demanding he step into those watery depths. His head felt empty, his heart demanding something, he couldn't be sure but suddenly he felt the waves licking at his toes. The ocean was dark, nearly black except where it reflected the moon's beautiful rays. It felt cold against his feet, yet soothing, making him want to be enveloped by it. The voice egged him on, curiosity demanding he find the source as he stepped deeper and deeper until his knees were fully submerged.

_Is this what my mother felt when she died? The cold, soothing embrace of the ocean, pulling her deeper and deeper to her watery grave?_ He wiggled his toes, feeling the soft sand shift and cover his toes. _Maybe… it wouldn't be so bad. To die here in the kind embrace of the sea. Maybe then my heart will stop aching. Maybe as the depths swallow me, it will swallow my pains and sadness._ He wondered, taking another small step forward when suddenly the voice stopped.

Eren looked up, gasping at the sight before him.

Right in front of him was a bubble with what looked like a figure inside. It was large, a barely tangible sphere above the water, an iris of luminescent blues, greens and yellows swirling around the dark figure with an intensity that nearly made Eren pee himself. The lights slowed and began to flicker out of existence like fireflies in the night, few remaining to highlight the figure. At a quick glance, he realized that it was a person sitting in the bubble, beautiful ivory skin gleaming in the moonlight. The bubble was cloudy, unclear and blurring many parts of the person, but he could see their face.

The man, he could clearly tell it was a man now, had a youthful and angular face with straight black hair styled in an undercut. Narrow, dull blue eyes stared back at him with what he could only compare to _delight._ The man's skin from what he could tell was white, almost like the man had never seen the sun. His nose was dainty and small, turned up a little at the end in an adorable fashion. His pale, thin lips were set in a smirk, giving a peek at sharp white teeth. From what Eren could see of the mysterious man's chest and shoulders, he had very well developed muscles. What confused Eren was his ears, they were dark blue, and looked more like a webbed fin then an ear.

The bubble rippled violently for a moment, the stranger's hand suddenly hitting the inside. The strangers' palms were also white, but Eren could just see a dark blue color on the tips of his fingers and towards the back of his hand. He also noticed that the man had claws, dark and deadly looking as he attempted to grab the bubble. _Who… what is this man?_ Eren wondered as the bubble seemed to grow closer. _Is this a dream? Am I still asleep?_

_How convenient. It's like he was waiting for me to come pick him up._ Levi thought as he stared at his soon to be mate. The boy had grown wonderfully; baby fat has gone to reveal lean muscles, beautiful eyes still as green and innocent as before. However, he could see the weight of life starting to weigh on him, no doubt the struggles that existing in society brought. His hair was dry, something Levi has only seen a few times and it looked utterly soft to the touch. His lips were also a focal point that Levi knew he would enjoy. _The things I can do with this boy… simply delicious._ He had taken the liberty of using some magic to impress his human, knowing that most humans did not see a sight like this every day.

However, the bubble he conjured was annoying, constricting his tail and not giving him free movement. _Compared to the things I will be doing to this brat on the true moon, these fleeting moments of annoyance and irritation will be very much worth it._ He smirked, loving the boy's expressive face. _He's adorable. Now how do I convince him to come with me to be my mate? Can halflings have children? Do they have tails when they will it to be?_ Levi wondered, but realized he could easily ask Hanji later as she had an extreme obsession with humans and halfling biology.

The boy wore some type of white cloth across his chest, the one end covering the shoulder but the hole seemed to be too big for both. His creamy legs looked soft, and Levi wanted nothing more than to bite into one of those blushing thighs. _Fuck, stay on target. Surely the brat will let me ravage him after we get home._ He thought with a nod, staring down the boy before letting out a long croon, hoping to entice him forward.

Eren startled at the noise, but soon found comfort in it, stepping closer before his rational mind stopped him. _It could be dangerous… I definitely should go back inside, maybe this is who my mother always warned against?_ '... He will take you away from me…' Her words rattled him and with a start, he backed up, snapped out of his reverie he scrambled backward until his feet were in the safety of damp sand. The man, the _creature,_ crooned louder, eyes narrowing the farther he backed up. He did not stay on the beach long, his feet suddenly becoming too hot, demanding anything to cool them down as they ached. Eren quickly found his feet planted in the sand of the sea, sighing as the heat disappeared. _What the fuck was that?! It felt like my feet were burning!_

Another croon left the man's chest, causing the boy's eyes to snap back onto him. The man's eyes softened at this and he flicked his wrist, water suddenly bursting forward and around the bubble, obscuring his view completely of the man. The water twisted and turned around the bubble, slowly receding from the top to show the man standing there, waist swallowed by a tunnel of water constantly flowing beneath him. _What the-_ his thoughts stopped as he really looked at the man, mind blanking when he saw that the man had fins flaring from his arms. _Fins… why…? Wait…_ He could see now that the man's whole back and his sides were a dark blue, fading into white on his stomach and chest. _What is he!?_

A hum of approval left the merman's lips when he realized the brat was checking him out, he filled up his spinous dorsal with blood, a clear mating sign as he crooned once more to the boy. Eren was blushing as his eyes traveled lower but realized that the man had scales the lower he got. They seemed to disperse the higher up the body he traveled, all of them a dark blue against the white of his stomach. _Is this… a mermaid!?_ _Well, I guess_ merman_ in this case._ His stomach and all of his underbelly were white with only a few specks of dark blue, probably so that predators looking above wouldn't be able to see him against the light of the surface. _Great, maybe I can count his teeth as he eats me since my knowledge from working at the Aquarium seems to be kicking in. Flipping in. Swimming in? Why am I debating this right now!?_

The merman's eyes seemed to sparkle, glowing internally as he stared at the boy, Eren couldn't help but be captivated by it. _His eyes… so beautiful… this has to be a dream._

_"The eye of the sea is looking at me…"_ Eren murmured, slowly moving closer, feeling like a slave beneath the other's stare.

**"I can take you there if you only dare!" **Levi practically purred, holding out his hands for the boy. _Come to me._

_"I've reached out into the darkness long enough now it reaches out to me!"_ Eren sang, stopping for a moment as he realized that this was the pull he has felt all along. _To the sea… this man is the **sea **…_ His eyes were intense, Eren unable to keep looking anymore shut his eyes, still able to see the light coming from the man. _Wait, why the fuck am I singing? I don't sing! You know what? Whatever. This is a dream anyway._ With that thought firmly in place, the urge to sing for the handsome merman thing was pushing up inside him, higher and higher until it seemed to bubble over. _Fuck it._

**"I am the sea and I'm calling! Look the sea in the eye!" **Levi sang back, near growling when the boy looked away. _Be mine, look into my eyes._ **"Hear me now, don't fight back or this ocean will be your watery grave, and the sea, it will entomb your barren bones for eternity, forever and eternity!" **His voice was like the rolling waves, deep and powerful, causing shivers to run up Eren's spine. He did as asked, as _commanded_ and opened his eyes, feeling enraptured by the look he was giving him._ Is this… my death?_

_**"Down, down, down the eye of the ocean sees you! Down, down, down the depth of the ocean owns you…" **_They both sang, Eren taking the last step until he stood before the merman. Levi purred and pulled the boy into his arms, feeling the warmth of his caramel skin. _I can't wait to mark him up, to make him my own._ Eren even took the time to touch the beautiful merman before him. His defined back, the silky black hair, all of him. It was cold to the touch but smooth and Eren could see the muscle in every aspect of his body._ He is simply gorgeous. Even his voice is beautiful. Damn, thanks brain for the visuals._ Eren thought, staring up at moonlit eyes.

**"Take my hand, together we dive!" **He sang, holding it out for his new mate. Eren was hesitant, looking from Levi's face to the churning waters around them. _Where will he take me…? This beautiful merman isn't a siren, is he? The ones that eat people? Does he eat people? Is he going to eat me?_ Eren thought worriedly but then realized this was a chance of a lifetime. _When will this ever happen again? I can go back to taxes, to an empty house, and boring classes for a major I have no true interest in._ He thought, looking at the small house he called home for so long.

The roof was tattered, needing many repairs to fix the shingles. The once yellow paint was a musty white and cracked from years of sun exposure and no touch-ups. The siding was falling off piece by piece and the window in the front was still cracked from the teens who threw a frisbee at it. _I'm barely living now. I barely make enough money from my jobs to fix anything on the house. I never have time to do anything but work anymore. But… if I go with this merman… will my life finally be worth living?_ Eren wondered and looked back at the hand held out for him.

The clawed nails look dangerous and sharp, ready to rip into flesh like a hot knife through butter. _Yet he hasn't laid a harmful hand against me._ It was then Eren realized that this merman could have outright dragged him down, could have killed him already. It was at that moment Eren decided that this fate was inevitable, he was always called to the sea for this reason. He closed his eyes and leaned against the mers chest, nuzzling into his neck. His hand slid against the smooth skin, trembling at the low growl of encouragement that hummed through the mers chest. He tentatively felt every muscle beneath the skin, moving up the mers inner arm and wrist all the way into his hand, sliding them together and gasping when the other suddenly gripped his hand.

_"I'm ready to dive…"_ Eren murmured, voice sweet and innocent to Levi's ears. Levi trilled and nuzzled the boy's hair, enjoying how soft it felt against his sensitive skin. _How cute._

**"Be warned my friend an angel and a mermaid are never the same, are never, ever the same!" **Levi growled, voice guttural as the smell of mate filtered through his nose. He couldn't promise that he would be gentle, mers, in general, being a rather rough species, mating being a frantic affair of lust and yearning. He couldn't promise the boy that he'd be able to come back to his home, to his friends. But he could be truthful, never tell a lie to his mate. Eren shuddered at the sound and nodded, eyes squeezing shut as he wrapped an arm around the merman's neck.

_"I'm ready to die…"_ Eren whispered, legs moving up to wrap around the man's thick waist. His bare feet and thighs felt every scale, each one smooth and causing tingles to wrack through his body. The merman clutched him securely, hands moving to his thighs and squeezing the enticing flesh with vigor. _Fuck, it's soft… like nothing I've ever fondled before._ Levi couldn't believe his luck, experiencing the more fun aspects of mating with a human will surely be a lot more interesting with all this soft flesh. With a smirk towards the unsuspecting human, he dove backward and into the sea, disappearing into its mystic depths with a single push of his mighty tail.

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**Heyo so comment and tell me what you think! Open to suggestions and ideas on this story or even other stories!**

**Also, please support my dumb ass and buy me a $3 coffee. Cause you love me. Right?**

** hPKJrwQfk**


	3. Monster of the Sea and Night

**... hello. Just got back from Japan and am really feeling that jet lag so here is my work. Uh... you may have noticed that I extended the fic. It was supposed to be 3 chapters... I think it will be five. The next chapter is just smut and maybe some mom action, and the last being how their life is in a year. yay. I hate myself someone end me. anyone if yall had any ideas for things you'd like to see in this fic or in other fics, or basic plot ideas, or want to yell at me for being so fucking sporadic, comment down below**

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**_Last Time On Aquarium: Eren hears the beautiful song of a merman and walks to the sea, only to be trapped there by the steely gave of our resident grumpy mermaid. Shameless singing and Eren gets swept into the briny deep by a very horny merman._**

**_This Time On Aquarium: Now Eren is introduced to the cave his future resides in, some miscommunications and understandings are reached as a secret about Eren's past is revealed, and a new question is posed._**

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The swim down was not as bad as Levi thought it would be. He was unaware that humans couldn't hold their breath for that long and was rather concerned when the boy began struggling against him. At first, he thought the boy was trying to escape him, but he just needed air. Levi quickly remedied the situation, opening the other's mouth and giving him the life saving air he needed with his own. This seemed to shock the younger but he accepted the air pliantly, tapping Levi's shoulder every minute or so when he needed it again. As the pressure increased, Levi put a protective charm over his to be mated to ensure he wouldn't get crushed by the ocean's pressure.

Eren mostly kept his head on Levi's shoulder as they descended, only coming up to get more air, but Levi didn't mind it one bit, enjoying the silky strands he had instead. They moved towards the surface once more as they started getting into familiar territories. When they had finally made it to their destination, Levi was all but humming in elation, wanting his human to see the cave he had chosen for them. It was far enough from the mainland that humans did not come here often, and it was small and secluded, giving privacy and ensuring the raven that he would be able to see any oncoming predators or challengers nearby. It also led to the castle at the very bottom, carved from the rock that jutted out of this islet.

It was uninhabitable by humans, a rocky ledge with only enough space for a few trees and flower bed on the outside of water. But underneath it was big enough for a whole family, pups and all. On the side was a slope of sand, tapering off into the ocean and shallow water to connect it to the other small island in view. _If he wanted to, the boy could walk across with little to no trouble. _Although Levi doubted he'd be able to do much walking once he was done with him. He continued forward, finding the opening just big enough to fit both of them and moved through the twists and turns smoothly, having memorized every nook he could before grabbing his human mate. The boy tapped his shoulder again and he was quick to slot their lips together and give him what he needed, a warm feeling burning in his chest at the fact that he was of use to his human. _Need me._

A cave buried under the water, large and with a perch appeared before them but that wasn't what Levi was looking for at the moment. He swam up and found the surface quickly, cooing at his mate who was gasping for air beside him. _This is more like it. _The cave was just below sea level, an air pocket connected to the surface with many shallows deep enough for Levi to move freely in, but patches of dry rock for his human to rest on if the water didn't suit him. In the back was an opening to the island above them, during the daytime it would let in sunlight and fresh air for his mate. During the night the moons haunting rays slipped through and bathed all below it with the ethereal light. Although the light was not necessary, Levi had attained fire and put it in one of the dry corners surrounded by a mote of clear water that would forever be lit (according to Hanji anyway) to warm his mate. He had made a nest for him both in the water and on the rock. The one on the land made of palms leaves and moss, as well as a few blankets Hanji had once scoured from sunken ships, they were dry and Levi was amazed at how soft they were. Hoping his mate would be pleased with them as a nest. And of course should he sleep in the water with Levi, Levi would serve as the nest for his human mate.

When he heard a gasp he looked down to see Eren was looking around as well, mouth agape and eyes sparkling with wonder. "...Beautiful…" Eren murmured and reached a hand out to touch the phosphorus algae on the underside of the ledge, glowing minutely from beneath them. He looked up at the merman and back at the bed of rocks and shallow dips in front of them. "Is this… your home Mr. Merman sir?" He asked, looking back at the merman's glowing eyes. Levi hummed and sniffed the boy's neck, enjoying the pure scent that lay there.

"Call me Levi. And yes… this is our home now. Does it suit you, Eren?" Levi asked, massaging the boys' thighs and licking at his ear with small swipes. _Delicious. _"Ah… _our_ home?" Eren questioned and Levi nodded against him. "Yes. You will be living here with me from now on. If there is anything else you need to be comfortable we can go back to land and you can grab it." Levi explained, swimming into one of the shallow pools next to the nest so his mate could inspect it.

"I… I don't understand. Why am I here? Why did you choose me?" Eren questioned and squealed in panic when he felt something slimy grip his foot before realizing it was merely a piece of seaweed. _For a dream, this feels hella realistic. _Levi smirked at his fidgeting and got comfortable, tail wrapping around the boy's waist and legs to still his movements.

"You're my betrothed, of course. Do you not remember me? You asked me to marry you many moons ago." Levi murmured, hands traveling back to the boy's trapped thighs to squeeze the soft skin. _Fuck he is so cute. I want him squealing on my-_

"Betrothed!? _Marry _you! When the hell did that happen!?" Eren gasped, feeling the merman fondling his thighs. _What exactly does this guy plan on doing with me?! _He voiced his question and Levi huffed, hugging the squirming human to his chest. The boy's back was now pressed against the rip mers chest, allowing Levi to do as he pleases with his hands running up and down Eren's toned stomach.

"I plan to mate you, Eren. To open you up and breed you. You are a halfling so I'm not sure if you can even have pups so I will make sure to bury as much sperm into you as I can." Levi whispered the filthy promise directly into Eren's ear, hot breath causing Eren to shiver. _Wait… he wants to… do _**_it_**_!? What does he mean halfling!? Breeding!? Ok, this feels too real. _Eren quickly pinched his arm, surprised at the very real pain in his arm. _Uh… what? _Eren's mind was swimming (heh) with questions and Levi seemed to understand at least that. With a nip to the area behind his ear, leaned back and brought the confused human with him.

"Do you remember meeting me at all?" Levi asked and Eren quickly shook his head, getting an irritated sigh from the raven haired man.

"Damn brat. Forgetting me all of a sudden…" Levi grumbled and ran a hand through his hair to slick it away from his face. "Well, when I was about 11 ultra cycles and you were 5, you got dragged into the water and I saved you. We talked and you spoke of some bitch named Ariel. I don't know what you guys are to each other now but I don't give a fuck since you're mine, I won't hesitate to kill anyone who tries to take you from me. Anyway, then I sang and we talked. I made you a ring of shells because you said it was your dream to marry a mermaid and you asked me to marry you. But then some woman came down and when she saw me she started screaming and I was forced to leave. I never thought much of it until a few ultra cycles ago." Levi explained, his storytelling skills as shitty as ever. Eren wracked his brain for any sort of memory of this, his mind only supplying a few blurred images of a dark figure holding him and some singing. However, if what Levi was telling him was true then it would make sense as he did remember his mother crying and yelling about someone trying to take her baby away.

Levi watched his expression carefully, trying to gauge how the other was feeling about this whole scenario. His tail tightened slightly around the boy's thigh when he felt him squirm in his grasp. "Wait… what do you mean halfling? What is that?" He questioned, looking at the silver pools of Levi's eyes. Levi quirked a brow, surprised that the boy didn't already know this. "Well… a halfling is exactly that. Half human, half Merman. Did you not know this?" He asked and Eren's mouth dropped in surprise. _Me… a mermaid!? What is he even talking about?! That means that one of my parents had to be a mermaid! That's…_

"Not possible. My parents weren't mermaids! My mom drowned! A mermaid can't drown! And my father didn't set a single foot in the water ever! I, Eren Jaeger, cannot possibly be a merman!" He vowed, noting how Levi suddenly stiffened around him. "What? Why did you suddenly stiffen?" Eren questioned, feeling a cool hand on his chin to move his face up. Levi's eyes were wide in shock, his eyes flitting about his face as if seeing it for the first time.

"...Jaeger?" He asked quietly, clearly searching for something in Eren's eyes.

"...Yeah… why..?"

"Is your mother called Karula?" He questioned, eyes widening impossibly further when the boy nodded in affirmation.

"She went by Carla though, said it was easier to spell." Eren said in jest, still unsure as to what was going on. "Wait, but how did you know that? I never told you her name…"

"Oh Mariana… this is priceless. I am betrothed to my missing betrothed…" Levi whispered, a slow chuckle escaping him as he leaned down to nuzzle the boy. "I understand… she must've hid as she did to give birth to you. But in order to survive, she would've had to come back to the water. Eren," He addressed the boy, who was staring intently at the fish prince, "Your mother is Princess of the Jaeger clan, she was supposed to be the mother of my betrothed when they were born but left without a trace when her suitor was revealed. In that time she must've already met your father and she gave birth on land. You… the boy who proposed to me on the beach… offered to be my mate… were always meant to be mine." Levi explained, a hand slithering down onto the fabric of Eren's soaked rubber ducky boxers.

"Wait… but my mom drowned! She is dead because she drowned…!" He argued but Levi shook his head, sharp teeth nibbling at the smooth flesh of his neck. "Did they find a body? I doubt it because she has been released from the ice caves quite a while ago." He murmured and Eren shot up.

"Are you telling me my mom isn't dead!?" He shouted, earning a small but forceful nip to quiet down.

"Not so loud! My ears are sensitive dammit! But yes, last I heard as soon as they released her she went to shore but was unable to change back into a human. Based on the smell of it though she was probably guarding the shoreline leading to your house. Her scent was aging but she wasn't too far off. She'll probably flip fins when she realizes I took you away after all." Levi answered, hand slithering into the boy's underwear to gently palm his cock. Levi was surprised at this, figuring that humans would carry a protective pouch for their dicks, however, Eren's dick was out in the open for all to see. _Do all humans leave their junk out? Or perhaps he is just so aroused it already came out?_

Eren's head was reeling, the news hitting him all at once. _My mom… is alive? _Eren let out a surprised gasp when he felt Levi's hand in his underwear, suddenly groping at his dick and began to squirm. "Ah wait! What are you doing? Can I see my mom?!" Eren shouted, attempting to free himself but to no use. Levi, annoyed with the fabric that didn't allow him to see his mate in full, quickly took a claw and ripped them off, purring when he saw the cute thing. "Mmm. Don't talk about your mom when I'm touching your dick. That's weird. But yes, after our pairing is finalized I'll take you to see her." Levi responded distractedly, suddenly staring very intently at the delicious looking skin on his neck.

_"_Wait reall- ah?!" Eren gasped again but was effectively silenced by a long tongue suddenly curling against his nape. He felt hot, his skin flushing all over as the first pulses of arousal began to harden his dick. After a few moments of Levi's harsh sucking against his sensitive nape, Levi slowly moved on to sucking on the spot behind his ear. He had Eren mewling and panting on his lap, his hand now lightly stroking the boys cock for how well behaved his mate was being. Eren let out a moan when he felt the merman nip at his ear, trembling when he was pushed around until his back was to the mermans chest. His strong tail was smooth and warm, wrapping around his legs like a living vice, leaving the mermans hands to move around as they please. _Ugh… there's no way I'm gonna last like this. It's been so long since my last one night stand. Since Jean. _Eren quickly felt his mood drop at the thought of that horse faced bastard but was quickly distracted by a very well placed nip to his erotic spot. _Fuck!_

"Wait… Levi what about… nngh… I don't even know you! We can't have… sex yet!" Eren managed to get out in between fingers pushing into the slit of his dick and a hand to play with his balls. Levi made a sound of confusion and squeezed Eren's poor nuts a little too hard, a shout leaving the boy at the pain. Levi let go immediately but continued to gently trace them with his fingers. "What is this?" He murmured in a voice that nearly had Eren coming right then and there. _What is what? _He thought, voicing his question to the merman only to feel him cradle his balls once more. "This. It's soft." He answered immediately.

"Those are my balls! There sensitive so please don't squeeze too hard…" Eren whimpered, not sure how to feel with the merman's claws gently touching his sack. Levi resumed licking at his cheek and neck before his lips were suddenly at his ear. "And what are they for? Do they… _also_ feel _pleasure." _He purred and this time Eren bucked into Levi's grip, a steady stream of precum starting to run down his shaft. Levi cooed in his ear and began to pump faster, feeling his own cock begin to slither out of his protective slit in his excitement. "Answer me, Eren. Do you feel good?" He whispered huskily into the boy's ear, enjoying how he trembled so prettily against him.

"Ah… they carry my… _stuff." _He gasped, looking over his shoulder to see Levi staring at him. "D-do you not… have a place to keep _it?"_ He asked, honestly curious now as to what mating with a merman would entail. Levi huffed, a small smirk curling at his lips as he licked his mate's cheek.

"Keep what? What is my little axolotl going on about?" He questioned, moving the boy around so that they were facing one another, much better for conversation. His hand left the boy's dick, much to said boy's dismay, and curled around a plush thigh, squeezing the flesh amorously but otherwise not distracting the boy anymore than necessary.

"Well… you know… it holds my sperm." Eren revealed to the merman, desperately willing away the blush on his face. _This so embarrassing, wait does he not have balls? Does he even have a penis?! Perhaps sex is different for him then it is for me? _Levi hummed in affirmation, knowing what the boy was talking about but... "Why is it on the outside? Aren't you worried about it getting fucked up?" Levi asked, looking down at the boy's dick with more curiosity now then lust. "When you walk around, doesn't it flop around like a beached dolphin? Doesn't that hurt?" Eren blushed and sighed, resigning himself to the reality that for some reason he's explaining his private parts to a goddamn merman.

"I mean… sometimes yeah but when I wear underwear it kind of holds it still so it doesn't do that." He answered, steeling himself for the embarrassing questions that are sure to come.

"So… where exactly _is _your penis?" He brought himself to ask, not looking into the mermans eyes but rather at his lap, causing him to blush upon seeing his own leaking dick. _If I blush any harder I'll surely catch on fire! _"Heh. You look like a cute crab right now." Levi noted, pinching the boy's cheek and earning a few slaps on the shoulder. _"Shut up! _This is embarrassing ok! I don't tend to talk about my private parts to people, especially to a handsome merman I just met!" Eren shouted, earning a small nip on the shoulder for being loud but the look on Levi's face was slowly becoming less lustful and much more gentle.

"Don't worry, in a week I'll have seen, licked, fucked, and touched every part of you. Surely you'll be good then yes?" Levi listed off, each filthy word rolling off the elders tongue like a dark promise. Eren squeaked, hiding his head in his hands, body squirming to try and turn away. Of course, the incessant wiggling had Levi's cock finally slithering out of its protective slit, prodding gently at the bottom of Eren's balls before gliding up towards his hole. Eren paid no attention to the initial contact, but full on shrieked when it suddenly pulled at the rim of his hole for a moment. _"What the fuck!?" _Had Levi not been gripping Eren the way he was, he is sure that Eren would've catapulted across the cave.

Eren looked around wildly to try and see exactly _what _had just been touching him so... _inappropriately, _when he felt something hot and thick prodding at his lower back. A quick look behind him had him tensing, embarrassment coloring his cheeks a deep red when he saw Levi's penis. _Oh shit… does he _really_ think _that_ will _fit_ inside _**_me_**_!? _The cheeky merman smirked at his reaction and gave him a little nip on the neck. _I think I broke him. _He thought merrily, happy that his penis was indeed adequate for his mate if the sudden twitch of the human's own organ was anything to go by. Eren whimpered, staring at the throbbing organ currently resting against his ass. Levi's dick was easily the length of his forearm, nearly as thick as his arm too. The overall shape was actually rather odd, looking more like a long ass tongue then it did a dick. It was bright pink, contrasting greatly with literally every other color on the mysterious merman. _Is that… really his dick? Surely he doesn't think that will fit inside me! _

Levi let a hand palm down to the boy's butt, kneading the flesh gently and enjoying the plush and soft skin generously. The feel of hands on such a place had Eren groaning, tingling sparks zipping through his body like a rocket with each knead and press. _"Ah… _you don't… nnh… think that will fit in-inside me… do you?" Eren asked, giving an awkward chuckle towards the end but not liking the confusion on the mers face. "Of course it is. You're a halfling so you're built to take me in every way. Don't worry, I asked Hange and was assured that it won't hurt you." Levi soothed, petting the boys drying hair. "I learned a lot of things from her actually. You are most likely capable of having pups, it just requires _a lot_ of my seed so we won't know until we've fucked a lot. But there is a chance that you can't have them but we won't know until I breed this sweet _sweet _ass." He growled the last part, swatting at the unsuspecting boy's butt and enjoying the sudden moan the boy let out.

Levi smirked at this and began palming the now blushing cheek with a gentle hand. _How cute. _ "Levi! That's inappropriate!" He reprimanded, trying to ignore the very real want that started to creep its way into him by instead reaching back to shield his ass. This somehow ended up holding Levi's frisky hands in place much to Levi's amusement. It was silent for a moment, Eren peering down through his lashes at the merman, noting the tender look in his eyes. _Is this… really happening…? _His heart thumped wildly at the prospect of having sex with the sinfully handsome merman. It's been a couple of years since Eren had dated Jean, and many nights Eren would stay up due to sheer loneliness. Craving affection as he sat alone in his room. _This is probably a horrible idea, but maybe it won't be so bad. I've missed the intimacy of sex, of being with someone. Maybe it'll do me good to let go and give in a little._ _Am I his first? _The thought of Levi being with someone else had his fists clenching hard enough to turn white. Levi seemed to sense the sudden shift in his aura and began to tentatively pet his lower back with one hand while the other drew mindless patterns over Eren's hand. _Just as he was starting to relax. Did I do something wrong?_ "Eren?" Levi called out questioningly.

"Am I… have you had sex before?" He asked, kind of embarrassed at the sudden jealousy flaring in his gut but not enough so to not voice his problem. Levi cooed, the sound vibrating low in his gut as he leaned forward and nuzzled his mate to be's neck. "Are you jealous, my little axolotl? There is no need to be. I've had no other, and will have no other except you." He vowed, giving a small smile when Eren began blushing again. "Ah… so I guess I'll have to teach you what to do…" Eren murmured, the obvious implication riling up the merman with jealousy. It took much self-control to be mindful of his claws as he squeezed the sensitive flesh beneath his hands. "You… you've laid with another? You've been claimed by another?!" Levi growled, voice teetering on dangerous as keen eyes searched for the mark but found none but his own. Confusion replaced anger and jealousy, his instincts forcing him to check over the male, snuffling at his neck and wrist to find only his and Eren's scents. _What?_

"I-I…" Eren stuttered out, confused by the sudden hostility, "I have… but I'm clean. I used protection and got checked out afterward and I have no diseases. Soo…" Eren finished quietly, misunderstanding the mermans actions. "But you have no mark. Did they not wish to claim you?" Levi asked in confusion, brow scrunching together in what Eren thought was a cute manner before Eren tilted his own head. "Claim me? Mark? I mean, marks fade after a few days. Are you talking about Hickeys? Like these?" Eren pointed to the hickeys starting to form on his own neck.

"No, I mean the mating mark. I don't see one."

"Mating... mark? The hell is that?"

"... You don't know what a mating mark is? Why would you mate without gaining a mating mark?" Levi asked incredulously. Eren huffed, still not understanding what he's talking about.

"'Mating' as you keep calling it, is very… uh… fun. I mean, I'm not a cock addicted whore or anything but It's a great form of exercise and stress relief." Eren explained, starting to think that perhaps there's a different stigma around sex to Levi then there is for Eren. Levi looked pretty shocked, eyes contemplative as he looked at the human's neck. "Then," He started slowly, almost as if he was unsure how to proceed. All the lusty touches were gone and instead replaced with comforting touches to his lower back. "You have multiple mates? You remain unclaimed?" Eren wasn't sure, but Levi sounded a bit vulnerable here, the merman refusing to meet his eye.

"I think there might be a cultural difference here. Do you understand the human concept of marriage? You mentioned it before but I want to be sure." Eren asked and Levi nodded.

"It's our equivalent of mating." He answered and Eren nodded in understanding.

"I see the problem here. In the human world, sex and marriage aren't the same thing. Uh… there are some people who would rather wait until they are married to have sex, but there are some, like me… uh… where marriage isn't the major component. I don't go around having sex with everyone I see, but if I am interested I'm not opposed to it. I don't know what a mating mark is, but if it's something permanent to show your spoken for, that would be marriage. So no I've never married anyone before." Eren explained, happy to see Levi looking into his eyes now.

"So… you have _mated..._ without _being_ mated? Do you not feel a longing for that person?" Levi asked, now feeling a little more secure knowing that Eren can still be his.

"Well yeah, that's why I had sex in the first place. But sometimes it just isn't meant to be. I've had sex out of love, boredom and just for fun. I'd rather have sex with someone I love, but I haven't met anyone in a while who honestly wants my heart so." Eren explained, starting to feel a little shy talking about all this with what is virtually a complete stranger.

"Wait, are you trying to imply that you wanted to have sex with me, _and _marry me? Honestly?" Eren asked, a little shocked but tried to give him the benefit of the doubt.

"Yes. I'd never mate with someone I didn't plan on being with forever. Merpeople mate for life, Eren. We chose someone we find compatible and spend the rest of our lives with them. We give them a mating mark, like your ring, to show that we belong together irrevocably. I choose you to be my mate. Will you also choose me?" Eren was frozen, eyes wide in shock at the explanation. _He had said stuff about marriage earlier but this whole situation is just so odd I thought nothing of it. _Levi began to gently knead at Eren's hips, grounding the brunet as he truly realized the situation. Here he was, soaking wet and practically naked on the lap of a beautiful, magical merman. A merman currently asking him to be his forever. _Did I fall into some fantasy novel or something?_

"I… I don't even know you… this is such a big commitment too…" Eren murmured, focusing on parts of Levi's face rather than looking into his eyes. The raven sighed and nodded.

"I know. I wish I could have courted you properly, but there isn't time for that now. Tonight is the true moon. I have to be mated by the time the moon cycles. This is the last true moon before next year, and I won't be able to mate during the next cycle." Levi explained, bring a hand up to gently bring Eren's face up so that he could look into his eyes. "I promise to you, Eren, I will do everything in my power to keep you happy. I will court you and spoil you, and you will never want for _anything. _As prince of the Trostinians, this I swear." Levi vowed, hope sparking within him at the empathetic expression on the brunet's face.

"What happens if you don't? Is there no way to hold it back, even if just a week? You know nothing about me, whether you could even like me." Eren asked, already knowing his answer, but wanting to be sure.

"I will become a monster during the next cycle. Inconsolable and destructive. It's some sort of evolutionary thing to ensure that our species will mate during our prime and find mates. By the next true moon, I will have already started to turn. That's why we are required to mate before our time, to ensure that no one will become a siren." The merman explained, face cringing as he remembered the last time he saw someone turn. It was a gruesome sight, their bodies twisted and corrupted as they mindlessly wiped out entire pods. The only escape is death for those who waited too long. _I should've been mated the last cycle, but my stubborn ass couldn't be persuaded. If only the law had been changed before, we would have more time._

"... There will have to be compromises. As cool as this place is, I'm going to have to go back to land. I also expect daily cuddling." Eren murmured, the mer perking up immediately, arms pulling the boy close as he buried his face in his collar bone. A deep inhale of his scent filled his lungs and he let himself relax, the worry he felt of losing his mate dissipating as he sucked at the boy's neck and rubbed his back. "Of course. This is a lot, but I will do everything I can to help you and give you anything I have." His voice a soft grumble as he began to scent the boy some more, hands bravely going back to the soft flesh of his ass.

Eren whimpered at the attention and tilted his neck to allow better access, hands tentatively going up to Levi's hair to pet the strands. The soothing touch caused an odd rumble from the merman, but Eren figured he must've liked it as he started to lick his way up to Eren's ear. "Anything?" Eren whispered, letting himself go and accepting that this merman will be his from now on. _That doesn't sound so bad. I wonder what mers do for courting?_

"Anything." Levi growled, giving one last nip to his ear before backing up enough to look into Eren's expressive green eyes. Eren looked away, feeling a bit shy now that the intense merman was only looking at him.

"I… um… can you kiss me… please?" He asked, staring imploringly at the hot merman. Levi tilted his head and let out a small, confused warble.

"What's kiss?"

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**MUHAHAHAHA**  
**I had more down but I had to cut it because it was getting long so have fun with this I guess. Please comment anything you liked, any errors or just general conversation and suggestions for future stories!**


	4. A Pleasure to be of your Acquaintance

**Last Time On Aquarium: Levi brought Eren to their new home, a cave he carved out for the boy. Eren gets an explanation and even finds out he's half mermaid, his mother being queen Karula, the mother to Levi's betrothed before she disappeared. Levi explains he must be mated this true moon, or he turns into a siren, a terrible beast that kills with reckless abandon. Sex and marriage explained and crossover between two different cultures and Eren asks for a kiss.**

**This Time On Aquarium: Eren and Levi do very little talking, much frickle, much frackle, Levi's dick was supposed to be a dolphin dick but now it's like a tentacle? Sorry?**

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**I have to clock in in 3 minutes I will fix in a few hours once I'm off enjoy**

**EDIT: Heyo just got off the clock for a bit. I'm gonna edit this a bit so if you are reading this now congrats you don't have to read the sucky shit I left unedited. Also if y'all have any questions about Levi's powers and shit or if you spot any continuity issues pls comment thanks! Enjoy! I don't know when I'll post the epilogue, maybe in a day or two but no promises.**

**Fun Fact: Christopher Columbus thought he saw mermaids in 1493, but from his description, they were probably manatees.**

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"What's kiss?" He asked, enjoying how red the boy's neck and collar were turning._ A cute red crab. Or perhaps he really is becoming an axolotl?_ Eren was gaping at him in astoundment, clearly thinking Levi insane.

"You don't know what kissing is!? But you kissed me before?" Eren questioned and Levi's face conveyed his confusion. "What are you talking about? When have I _kiss_ you?"

"On our way down here! You kept kissing me when I started running out of air..."

"When I gave you air? You need air again?" Levi was beyond confused at this point but decided that it didn't matter his reasoning, as long as Eren wanted something Levi would do everything in his power to do as his half mer wanted. With a tch he leaned forward and slotted his mouth with the boys, enjoying how soft the boy's lips were. They both sat still, Eren with shock at the suddenness and Levi with inexperience. However, after a few moments, Eren tentatively began to move, wrapping his arms around the mers neck and tilted his head to deepen the kiss. At first, it was shy but Levi is a fast learner and soon had Eren whimpering in his lap. Kissing Levi sent electricity bolting through his body, the warm frenzy of his hands roaming around Eren's lower back and butt causing warm tingles to bubble inside him. Eren whined, feeling the heady warmth of arousal slowly crawl through him, in search of something to consume. Eren was practically putty in Levi's arms, soft and relaxed against him, making sweet noises as Levi introduced his long tongue to the mix. Levi groaned against him when the younger began to suck his tongue. _I'm supposed to be giving him air yet he sounds more breathless than before._

Much to Eren's delight, Levi's tongue was longer than a human, thinner towards the tip and thicker towards the base. It curled against the boy's cheeks and wrapped around his tongue before gently tapping the back of his throat, Eren gagged for a moment, disconnecting the kiss before returning back to his lips with fervor. "Levi…" Eren groaned, hips bucking in pleasure as he began to rub his needy cock all over Levi's naval. Levi didn't mind this one bit, the boy's ass rubbing oh so nicely against his engorged cock in the process.

"So a kiss is when I fuck your mouth with my tongue?" Levi asked, Eren groaning and hiding his face in Levi's shoulder. "Don't say it like that! But yeah… it's how we show affection on land." Eren explained, planting several little pecks on his shoulder and neck before giving him a small kiss to his lips. Levi liked the feeling, the pure burning like a geyser in his gut that told him he needed more. He turned them over, the water around them warming as waves of magic flowed from the prince, his emotional state causing an upheaval of the control he had. The ledge they were on was very shallow, the sloshing water sometimes splashing onto his naked back, his legs unable to fit and therefore presenting his ass as if bent over. The boy gasped at the feeling of soft sand on his chest, nipples perking up at the constant rub as Levi repositioned them, his chest against Eren's back as he rubbed his dick against Eren's supple ass.

Levi groaned as the tingles of pleasure became a harsh current, pulling him to and fro as he continued his instinctual dance. The water mimicked his image, small waves crashing against the rock around his mate. "Eren… I'm gonna fill you up… gonna make you nice and round full of my pups." The prince groaned, looking down at the tanned back before him, the skin smooth and unmarked, muscles rippling beneath the fine flesh with every shuddering breath and whine from his mate.

"Levi… that's… please…" He begged, the words a mere whisper but Levi's highly sensitive ears picked up the plea as if he shouted. The mer surged forward, lips locking onto the boy's neck before him to continue sucking on the darkening marks he already left behind. The clawed hands holding him above his mate slowly lowered him until he was fully laying on the brunet, knowing the closeness and the weight would give Eren some security. Just as he thought, the boy made a little rumbling groan and relaxed fully beneath him. _How pretty and pliant he is._ Levi's chest grumbled out his satisfaction, hands kneading and massaging into Eren's sides while his mouth left love mark across his shoulders and back.

Levi's cock was pushing and prodding against tan thighs, trying to find that place deep within the brunet that would bring them both pleasure on instinct. Eren, upon realizing what was poking at his ass cheek, quickly spoke up. "Hah wait! I need to be stretched first!" He said quickly, trying to look back at the mer but found himself pinned underneath the weight.

"Stretched?"

"Yeah… you know… my asshole…" Eren murmured shyly but the merman made another confused sound so Eren sighed. "Let me do it then… can you get off for a moment?" Eren asked gently and Levi complied immediately, confused as to what the brunet was after. Eren slowly reached his arm back and felt between his cheeks, and once he found his hole he slid two fingers in. He let out a gasp at the feeling, imaging Levi's fingers instead of his and quickly began to finger himself, scissoring the twitching hole as his body began to prepare for mating. Levi felt his arousal grow as he watched the clear mating signs, Eren's beautifully arching back, his shallow breathing, the subtle twitch of his muscles under his skin, all of it aroused Levi beyond belief. But what really did it was seeing tan fingers dipping into his hole. The little hole spreading wide with each movement, begging Levi to fill it until it was red and leaking. He growled at the thought and quickly slid backward until his lower body was hidden beneath the water, hands gripping the boy's ass and burying his face there, the warmth comforting him as his mind caught up with his body._ What am I doing?_

"Levi?!" He ignored Eren's startled gasp, backing up only to see his fingers still in their place, but unmoving.

**"Keep going."** He growled, the brunet quickly doing as ordered as if by magic. If he looked back, he would see the dark aura surrounding his new lover, magic swirling about him in wisps as his eyes darkened to black and his skin began to glow like the moon. The sky outside began to swirl, a storm like no other about to hit the little island as Levi's desire grew and his control diminished. Levi didn't notice, black eyes focused on Eren's gorgeous asshole. He wanted it bad, he didn't know how he wanted it, but he had an instinctual need to help Eren stretch for him. Before he could rationalize what he was doing, his long tongue was poking at the rim before sliding in alongside Eren's digits, earning a surprised moan from Eren. Levi was only encouraged by the constant slew of his name being moaned so filthily from the boy's kiss-swollen lips. He stuck to the tip at first, enjoying the unique taste of Eren before he indulged, pushing his tongue as far as he could, earning a near scream from his sweet mate. Eren's fingers were quickly removed, leaving only Levi's thick tongue that slid across his walls and prostate. Eren was crying now, the feeling of his insides being licked so deep inside him nearly enough to paralyze him with pleasure. Levi seemed to realize just how much Eren liked this, from the way his hips were bucking and his inner walls were twitching to his moans and cursing.

"Fuck… thank you thank you thankyouthankyouthankyou-! It feels so good! Please don't stop! I'm gonna come if you keep… hAH!" Eren cried out when Levi's tongue pushed harshly into his prostate. Levi froze for a moment, tentatively doing so once more and earning a similar reaction. Levi soon began to lavish the little bundle of nerves with attention, his mate nearly screaming with satisfaction as the skilled tongue abused him.

"Oh yesyesyesyes Levi I'm coming I can't AGH!"

He came. Untouched he spurted his seed across the sand underneath him, the gooey substance immediately saturating into the water as Levi began to slow. The boy was panting like he ran a marathon, eyes closed as he calmed himself while Levi slowly slid out of him. With lewd squelching noises, Levi fingered the twitching anus and found it to be acceptable. His tongue had Eren's alluring taste, and he couldn't help but give the rim a good lick that sent a jolt through Eren's body, oversensitive and needy as he was.

**"Eren, it's time," **Levi growled as he climbed back on top of the boy, needy cock drooling and ready as it began to line itself up, instinctively finding the warmth of his mate. "W-wait! I… I want to see your face." Eren pleaded, unable to move from the mind-blowing orgasm and Levi's heavy body. Levi let out a growl and shook his head, a large wave crashing into the small island, briefly flooding it while the sky roared. Levi heard the crash and growled in defense, curling around the brunet to protect him.

**"We can't I won't be able to reach your hole from the front. You aren't a full mer." **Levi growled, voice powerful and causing the whole cave to tremble for a moment, a rock breaking off from one of the walls and crashing into the dark waters around them. Eren shook in fear for a moment, but it quickly subsided into his greater need to see Levi as he took him.

"Please, let me show you. I want to see you. Please, Levi." Eren begged, trying his best to turn but he could only side eye so much. Levi kept him pinned for a moment but seemed to find some sense as he lifted his heavy form long enough for Eren to unsteadily turn over. Eren gasped at the sight before him. Levi's eyes were pitch black, teeth serrated and long like sharks and the veins around his eyes and neck were a dark blue. The fins on his arms were standing tall, sharp and dangerous in an array of grays, reds, and blues. What caught his attention the most, was the palpable energy swirling around him. Dark and foreboding, the strands seemed to float about him like deadly jellyfish, all keeping their distance from the deadly predator that was Levi. He looked positively ferocious.

_Was I right? Will he actually eat me? We talked but I still know little about him… for all I know I could've been tricked until now._ Despite the scary thoughts that perhaps this was his end, he felt trust as he watched Levi's form. Eren opened his legs wide, thighs squeezing the smooth flesh of Levi's tail to wrap around him, bringing the merman closer. They stared at one another for the longest moment, only being brought back to reality when the claps of thunder seemed to shake them. Eren's hands moved up the mers body to caress his face, wanting to touch him more than anything at that moment. Levi's skin was hot to the touch, smooth and foreign he thumbed the veins around his eyes until they slowly disappeared, retreating back into the flesh as if they never existed. Levi's eyes began to brighten, a pinpoint of light right in the middle of his eye expanded as he looked at Eren's face. Eren didn't realize he was smiling, but Levi couldn't stop staring at the brightness that was his new mate.

**"Eren…"** Levi groaned, unable to stand it anymore, his dick slithered up the brunet's thigh and quickly found its target. The wiggling appendage dove in quickly, a loud growl echoing with the sound of thunder outside at the tight heat surrounding him. Levi was very glad he let Eren turn over because nothing in this world could be as amazing as watching Eren's cheeks darken and his mouth curl as he let out a whine. His fluctuating member was quick to burrow inside the delicious heat twisting and turning as he bottomed out in the panting male. Eren's hand never left his face, even as he muttered out a 'wait' that had Levi sitting motionless inside him.

"Ah let me get used to it for a moment. I've never had anyone so big and long… fuck I can feel you in my stomach." Eren complained, all with a slutty grin as his hands moved to ebony locks of hair. He couldn't get enough of the mer, his insides shook with pain yet pleasure warmed him and curled his toes. Seeing Levi's face as he took his virginity was also quite a treat, his eyes brighter than before and the power swirling about him began to glow. His serrated teeth were bared in a fearsome display, but Eren felt no fear. In fact, it was the scariness, the power Levi had that riled Eren up. This merman could utterly _destroy him._ His sharp teeth which hid the tongue that brought him pleasure, his dark irises that covered his usually grey eyes that looked at him not in malice, but in a vulnerable tenderness as he settled. Sharps claws that gently touched his sides were shaking, Levi's hand trembling with the effort of keeping still inside the vice of his ass. This man could obliterate him in any way, yet he was letting out broken croons to try and soothe him, little whines that we're hardly audible breaking through when Eren's rim squeezed a little hard.

Eren shook his hips and nearly cried at the pleasure it brought him. Levi's cock was smooshed right into his prostate, every movement just a brutal assault on the pleasure spot. "Levi, please move! I'm ready now!" Eren gasped, arms moving to circle his shoulders and legs wrapping around the base of his tail. The squirming organ thrashed in the water as Levi's hips began to thrust cautiously into the brunet.

"Eren… it's hot… you feel so good… my mate." Levi mumbled, burying his face in Eren's chest to try and ground himself. _Perfect. He's so perfect. He's all mine. Eren is mine. I'm his. He's so tight-!_ The two were a mess of limbs and erratic movement as they pleasured one another. They were fixing each other, giving each other what they needed. Eren felt that lurking emptiness he's had since Jean fill, and Levi felt the siren, the lurking madness their recede with each thrust of his hips. Soon, his eyes returned to him and with clarity, he saw Eren's face. Eyes clouded with lust, mouth open to gasp and cheeks flushed with pleasure, hair damp from the shallow water constantly flicking over his face as Levi rocked into him. He watched as Eren's hand shot down his chest and onto his leaking dick, stroking for all it was worth as he came closer and closer to the precipice. "'M gonna come… make me come…" Eren mumbled, hands pulling the raven down to lick into his mouth. "It's so good, I feel your dick throbbing, you're gonna come too aren't ya? It's ok, you can come inside, don't leave…" Eren murmured drunkenly, having a hard time keeping his head up as wave after wave of white-hot fire scorched him from within.

Levi couldn't believe how lucky he was to get such an attractive mate, his cock drilling harder into the younger male and ensuring to hit all his pleasure spots. He grinned at Eren's helpless cries, the gasps and moans were euphoric and Levi felt a pull within him. _I'm close, I need to mark him. Now._ With as much strength as he could muster, he pulled the boy off his mouth, desperately wishing he could continue when Eren began to whine and try to pull him back to that addictive mouth.

"L-levi…"

"Soon."

That was all the warning Eren got. Next moment, he felt lips against his upper shoulder, small pecks of reassurance dotting the skin before white-hot pain replaced it. Eren screamed, dueling instincts demanding he lie still for Levi and that he run from what brought him pain. _Oh fu-._ That was the push he needed, come pouring out his dick like a goddamn geyser and he blacked out.

**[Aquarium]**

"... en… en!" A voice called, the sound echoing and distant as Eren tried to figure out what was going on with a groggy mind.

"...ren! Eren!" The voice became more clear, and Eren quickly began to feel a burning sensation in his lower abdomen. The grogginess cleared and soon he opened his eyes, seeing the eyes of a frightened mer staring back at him. The relief was clear on Levi's face when he saw Eren looking at him again.

"Eren. Look at me. Are you ok?" Levi asked, worriedly snuffling about his chest and neck before moving back to the fresh mark to clean it with his tongue. Eren winced at the rough drag of tongue against the thrumming mark, but bit his tongue and let the merman calm himself. _Did I pass out? All I remember is coming and pain._ Eren felt sore all over, the kind of sore that came with a whole night of fucking. The thought made him smile before groaning when he felt a wiggling in his gut. _Is he..?_ Eren tightened his ass and was very quickly reminded that they had sex and that Levi was still resting inside him. Eren whined and Levi quickly left his neck to suck on his lips.

"What's wrong? Are you hurt? Hungry? Sleepy?" Levi rattled off, hand petting Eren's stomach and eyes locked on his mates face.

"Hah… you're still inside me…" Eren whispered, belatedly realizing their positions switched. Levi was lying next to him with his upper body propped up in order to lean over him. Their bellies touching with his leg thrown over Levi's tail to keep him closer.

"Yeah, I've been coming for 15 minutes now. I need to make sure the seed stays inside." He whispered as well, laying back down to gently pet his face. "You were so good for me, Eren. Thank you." He continued, a small smile pulling at his lips that warmed Eren to the core. He couldn't help but lean forward and kiss his nose, his cheeks, his eye lips, and finally his lips, post-sex relaxation making him feel like he was on cloud 9. _I can definitely get used to this._ After a few minutes, they just laid there staring at one another, Eren tracing Levi's features with his eyes while Levi did the same, hand trailing up and down the brunet's back in relaxed bliss. "Go to sleep, Eren. You'll need your energy for our next session." Levi murmured, his own eyes fluttering as sleep began to shroud the both of them.

"Next session?"

"Mating lasts for a few days Eren. We will be very busy making pups. Now sleep."  
Eren was about to protest but found the call of sleep irresistible, no doubt Levi's magic playing a part in it. _Ah well, I'll just tell him off when I wake up._ The sea was calm, as the soft sounds of Levi's breathing lulled the tired boy to sleep.

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**I really struggle with sex scenes. I don't get it I'll zip through every other chapter like it's nothing, but come to a dead halt that takes forever to write as soon as it stops being foreplay. Ugh. All well thanks for reading my supposed to be one shot porn that turned into 5 chapters. Sorry if the smut didn't meet your standards I really suck. Comment any suggestions for the epilogue and any questions you want to be answered there!**


	5. Surprise

**Last Time on Aquarium: They fucked. That was basically it.**

**This Time on Aquarium: A little insight into life for the two after they're mated, a surprise visit from someone in Eren's past, and Eren has big news to share with Levi.**

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**_hahahahahahahahaha you're getting this right now because I had 2 more scenes to write and realized that I was currently over 6,000 words so I split it into 2 chapters! Honestly, with the roll I'm currently on, I'll probably post the next chapter tonight, but you will def get it tomorrow if not. Anyway without further adieu enjoy this mess._**

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"Shit fuck!" Eren cursed for the gazillionth time, his finger red where he accidentally burned himself on the pan. Eren's is hunched over the counter of his kitchen, hissing through his teeth at the burn of his finger as he looked through a drawer for another band-aid. The last 2 months have been hectic for Eren. After spending 3 days hanging off of Levi's dick, Levi's hunger for him finally abated somewhat, enough for him to meet his mother. Eren, of course, was stressing out because what if she didn't like him? What if he fucked up? Levi assured him it was fine, and once he got there he quickly realized that she was no regular mother in law. She was the motherfucking queen of the Atlantic Ocean! The entire Atlantic ocean! After the shock that his mate is a motherfucking merman prince, he was then told that he is the next ruling monarch, with Eren being Levi's king. Oh and his mom barged in and began swearing up a storm.

To say Eren has had a bizarre time is an understatement.

His mother was very against the coupling at first, fearing he was forced into the mating but after Eren's initial reaction of just bawling into her shoulder, he explained that he actually quite liked Levi. She begrudgingly accepted since it's not like she could reverse it, the mark on both their necks were permanent. Eren was hella surprised that they didn't fade, but a silver line was left in there place. Now Eren had to tell people it was a tattoo whenever he went to the grocery store and ran into people he knew. Levi's had a hard time adjusting to life on the shore. He somehow got legs with magic or some bullshit like that (Hanji gave Eren a more "Scientific" explanation but he just chalked it up to magic and moved on). She told him how he can actively help Levi adjust and claimed that lots of leg exercise would help him. At first, they did swimming with the legs instead of a tail. It irked the prince to be unable to cut through the water as cleanly as before but Eren still thought he looked so smooth and beautiful when swimming.

While Levi practiced using his legs, Eren practiced his mer powers. According to Hanji, he may never be able to shift his legs into a tail like Levi, but only time could tell. Levi said it felt like an unbearable need to stretch, but Eren never felt it. However, he did have quite a few powers due to his royal lineage apparently. According to his mom, they carried a gene allowing for excessive healing and animal communications. This would be useful should there ever be a fish shortage where he could enlist the help of other predators or even convince fish to hop into his net. Of course, Eren could never imagine commanding a fish to kill themselves for him, it was pretty cool to be able to make fish do some pretty cool tricks. Every day he practiced holding his breath, swimming, hearing underwater. Much to his own surprise, Eren is able to hold his breath underwater for an hour and a half and every day he's able to add another couple minutes or so before he needs to come up for air.

Levi was very proud of Eren and supported him any way he could. It was a great bonding experience for the newly mated pair. Sometimes after a long day of work, (Eren somehow managed to convince his manager not to fire him after being a no show for a whole week), he'll slip into the shallows with Levi and just lay on the mers stomach while Levi gently floated about below the surface. Those were Eren's favorite moments, just relaxing with Levi, feeling the weightlessness of the water and the warm skin of his mate. Despite his attitude and empty complaints about how heavy Eren is, Levi loved it too. He would pet his hair and back and just hold him close all while humming or singing to him. Eren fell asleep on more than one occasion. One time they got interrupted by Erwin coming to discuss some important royal stuff Eren had no clue about, and you'd think they'd grown an extra 8 limbs by the way Erwin gaped at the two.

Apparently, it wasn't normal for everyone who knew Levi to see him so loving and gentle, so Eren was happy to know that Levi was relaxed while with him. Sadly for them, Levi had to stay in the sea for lengthy amounts of time. He had been ignoring his royal duties in order to avoid being mated to Erwin, so now he had to make up for them as well as all his new duties now that Kenny will be stepping down. The couple isn't sure what they are gonna do yet about housing arrangements. Eren can't stay underwater long enough to actually live in the palace, but the cave is just that, a cave with only a place to rest. Levi was disappointed that Eren didn't want to live there, thinking he didn't provide well for his mate, but soon understood why when he saw how humans lived in the first week on land. Yet Levi can't live full time on land due to his position as prince soon to be king. So right now, their arrangement is that when Eren has off from work for more than 2 days, he'll go to the cave with Levi. When that isn't the case, Levi will come to land and sleep there with him whenever he can.

It's been two days since he last saw Levi, and Eren missed him dearly. Not to mention he had quite a surprise for when he returned to him.

Eren sighed and stretched, looking at the dinner he probably ruined for his mate who may or may not even show up. The fish was a dark brown so Eren quickly turned off the stove and slid it onto a plate to decorate it._ Maybe he'll come back tonight. So far he usually leaves for 2 to 3 days so chances are he'll come back tonight!_ The thought made Eren smile, the warm feeling of love spreading through him as he thought of his grumpy prince who loved to cuddle. His hands unconsciously rubbing his stomach as he thought about the good news. He had a few more movies picked out for the mer to watch with him, having already shown him _'The Little Mermaid'_ and_ 'Aquamarine.'_ There is nothing, _nothing_ funnier than watching as Levi tried to out sing Ariel once he remembered that she was the mermaid that Eren loved as a child. He even demanded he be able to read the lyrics, and when Eren pulled it up he began singing along with the red-headed protagonist. He, of course, was trying to show off to his mate, and Eren couldn't help but find the entire ideal adorable. Eren couldn't stop laughing at him whenever he made a comment.

Saying things like, _"This_ is the mer you were rambling about? Tch, you had low standards. You don't still like her right? _Right?"_ "Why does she have 2 clams on her chest is she dumb?" "Her tail looks like seaweed. Also where the fuck is her dorsal? Her ears? She looks like a fish swallowed a human's legs, she looks nothing like a real mer." "Why is flounder so _fat_ and _yellow? Real_ flounder are_ flat."_ "What the fuck kind of palace is _that?_ It's so fucking bright the humans in Mitras could see it! Humans and their damn submarines." "That purple bitch reminds me of Hanji. Fucking Hanji." "Who the fuck goes to a sketchy ass cave, with some small, shriveled bitches all over the floor!?" "So she gave up her voice for some human dick? The fuck kind of sketchy ass trade is this?" "Eren stop laughing I'm serious! Ariel is a little bitch! I would beat purple Hanji to a pulp! She thinks making a whirlpool and turning green is gonna save her? I can command the tides, the skies, the creatures of the deep, _and_ the warriors of Trost! Bitch is straight _fucked."_

Eren had tears in his eyes from how hard he laughed throughout the entire movie. He liked_ 'Aquamarine'_ a lot more, but still made many, many comments about it. He planned to show him the _'Pirates of the Caribbean'_ next, as Levi seemed to like action films. But that involves his mate actually _being_ here. Eren unconsciously whimpered and rubbed the silver mark on his neck, hoping with all his might that Levi would be home soon. As if to answer his thoughts, the doorbell rings and Eren felt a bolt of excitement. _Levi!_

He runs to the door, quickly trying to fix his hair and ignoring the frilly yellow and red apron he wore. He had found it in the attack back when he thought his mom was dead and brought it out in memory of her. _Wait, Levi always comes through the sliding glass doors in the kitchen._ Eren felt disappointment flood through him, sad that it was probably not Levi then. So with a heavy heart, he opened the door, a surprised gasp leaving him when he saw none other than the man he hated more than any other. His grip on the door handle had the knuckles turning white, eyes glaring venomously as the offender rubbed his neck in nervousness.

"Hello, Eren."

_"Jean,"_ Eren growled, glaring at him. His hair was much longer than when they were younger, going nearly to his shoulders yet the undercut was still present. He also had a slight stubble of a beard, making Eren want to shave the scraggly bit off. Unlike before where Eren was smaller than him, they seemed to both be 6 feet tall, Jean gaining maybe an inch or two over him. "What do you want?"

"Can I come in? I saw you fixed the old place up-"

"No. What do you want?" Eren snapped, not mentally prepared to take on this type of problem. He felt the hairs at the back of his neck stand up, before suddenly he felt relaxed, if only for a moment before the tension came back. _Huh?_

"I want to talk to you." Jean eventually said, giving a pleading look when Eren merely raised an eyebrow.

"About _what,_ Jean."

"I… well… for the past few months, I couldn't stop thinking about us. About… that special connection we had. I miss it, Eren. I miss you. I think… I think I still love you to be quite honest." Jean confessed, wringing his hands out in front of him, but he looked right into Eren's eyes, trying to convey the seriousness of his confession. Eren was fucking_ livid._

"Is that so? Tell me Jean, who cheated on who? Who went and slept with my girlfriend at the time when I wouldn't get back with him? Who told me he didn't love me because I was too ugly? Who Jean!? Are you seriously going to try and pull this right now? What the fuck is wrong with you?" Eren yelled, growling at the end and trying to keep the tears fighting to roll down his cheeks._ This fucker… how dare he?!_ Jean looked guilty, and just shook his head.

"I was wrong. I was irresponsible and couldn't see a good thing for what it was. But I've changed! I have a steady job, and… I had tried dating again but every time I did, I always found them lacking. None of them are like you. So handsome, funny, smart, stubborn." Jean explained with a chuckle, hoping Eren would show any emotion but anger. That was not the case.

"Jean, you are a selfish dickheaded horse face in need of a good therapy appointment. You're abusive and manipulative and I couldn't see it then but I sure as hell see it now. Now giddy the fuck on out of here. I have someone who cares about me, I would never give him up. Especially not for you." Eren said proudly. Jeans face went from shock to anger, jealousy flaring in him at the thought of anyone having who he considered his.

"Who?! Who would date you?! Everyone in this town knows what a floozy you are! I made sure of it!" Jean screamed, anger showing the boy Eren remembered. _This fucker spread those rumors at the gay bars!? That's-_

"Me bitch."

Eren gasped, feeling the jubilant feeling that came with being around Levi surge through him like a tidal wave. He turned and smiled, holding his arms out for a hug despite the fact Levi obviously just walked out of the ocean. Levi did so happily, standing on his tippy toes to nuzzle Eren's mark against his to bring some comfort to the angry brunet. Eren melted into the embrace and accepted the marking thankfully, nearly forgetting his fuming ex right behind him.

"Who the fuck are you?" Jean neighed, face red with anger at seeing Eren so casually touching someone else. _He should only be touching me like that!_ Levi quickly stepped in front of his mate, eyes gleaming as he stared up at the only obstacle stopping him from cuddling his love after being gone for so long.

"Who the fuck are you? Why are you harassing my ma- no _Husband."_ Levi corrected, remembering the odd looks he got when he had announced Eren his mate. _Mate is a lover, boyfriend, and husband. Humans and their complex need to make shit up it seems._ The color drained from Jean's face as he looked on in horror. _Husband?_

"Y-Y-Your husband!?" He gasped, eyes immediately searching for a ring and found that immediately. The one on the short raven's finger was rather odd looking to Jean but was the second most beautiful thing Levi had ever been gifted. The ring was made from volcanic rock underneath the palace, specifically from the room in which Levi had been born. Eren had gotten Hanji to help him create the band, carving the rock into a ring and filling in the crevices with silver and gold, one small air pocket is filled with a small, turquoise stone, one meant to remind Levi of the ocean, but only reminded him of Eren's eyes. Jean had never seen anything like it and decided to move on, seeing Eren's ring was just as weird. Much to Eren's delight, the ring was a seashell that had been carved into some simple patterns leading to a small pearl at the very top. It was so simple, but it was also the ring Levi had given Eren when they had first met all those years ago. Levi never got rid of it, thinking of the boy sometimes in his room after a hard day while looking at the ring. He meant for it to be an 'engagement ring', learning from Hanji that the humans actually give 2 rings, but Eren was adamant that he only wanted that one. He had cried a lot, his memories of the whole encounter actually coming back to him as he looked at the ring. That night Eren had shown Levi what 'lovemaking' was. Levi had thought it was just fucking, but it was different in ways he never knew was possible.

"Yes, my husband. Now fuck off. Filthy fucking…" Levi growled, ushering Eren inside with a little spank to his eyes that had Eren 50 shades of red and closing the door behind him. Well, almost. A foot had somehow managed to find its way in between the door and Jean was trying to get through. "Wait! Eren! Please give me another chance! I will be a better husband then he could ever-"

Levi had enough. The door flew open, Levi standing there with void eyes, darker than even the deepest depths, fangs withdrawn and veins turning black as he let the anger control him. **He threatens your skill, attempts to take away what is yours. Show him his weakness. Show him your strength.** The dark voice whispered, Levi having a hard time concentrating on what he was actually doing. The sky darkened rapidly, thunder rolling through the clouds at an alarming rate as lightning began to strike the earth below. **He challenges you for Eren. We must kill him, parade his intestines around your territory, show them what will happen if-** the voice continued to whisper in his mind, the dark energy swirling around him in an aggressive and palpable display causing Jean to back up in fear and shock, falling flat on his ass when he missed one of the three steps onto their porch. **Kill him kill him kill him KILL HIM-** it chanted, Levi growling low in his throat in agreement.**_ I will slit his throat, dance in his blood, eat his heart all while he cries, knowing I am stronger, strong enough to protect my mate, my Eren. I-_**

"Levi." The voice brought him back to reality, the arms sneaking around his waist, the soft lips at his neck kissing the silver mark left there, the chest against his back all keeping him grounded as he slowly came back to himself. "I'm here, Levi. You're mine." Eren whispered, kissing his ear before moving onto his hair, nuzzling the wet strands that smell of the sea. Levi sighed at the affections, feeling the anger abate as he looked at the horrified human before him. Levi couldn't help but smirk at his wide eyes and shaking limbs, glad to see Jean feared him, knew him to be strong. Unable to resist, Levi called the water from the lawn to splash the bitch in the face, watching joyously as he screamed and ran from the yard and all the way down the street. Eren chuckled and shut the door before returning to his rightful place in Levi's arms.

"Who the fuck was that?" Levi asked, no bite in his words now that he felt calmer. He nuzzled his face into Eren's chest, the brat being nearly a foot taller than him while he was in human form. _It fucking sucks. When fucking I can't reach up to kiss his lips without him bending down._

"My ex. Remember when I told you about him? The one who mated with my mate at the time?" Eren asked, watching the recognition in Levi's eyes, as well as the anger. "The one who told you you weren't enough? That you were _ugly?!"_ Levi asked, spitting out the word as if it burned him to say. To be honest it kind of did. Imagining anyone refer to Eren with his bright eyes and smile, smooth skin and bigger heart as ugly was an act punishable by death. _I should've killed that fucking bitch._ Eren nodded and sighed.

"Yeah, that really fucked up my self-esteem for a very long time." Eren murmured, not letting it get to him anymore as he pulled Levi into the den next to the kitchen. "But it doesn't matter now. He's a dick, I don't care for him anymore. Besides, I have something much better." He said cheerily, sitting down on the couch and holding his arms out for him. "I have you. I could never ask for anything better." He said with a smile that had Levi's heart beating faster and faster. The prince immediately climbed onto his lap, feeling like he could breathe right for the first time in a few days as he relaxed. In times like these, Eren would often call him his 'little koala' with the way he clung to him. However, at the moment he chose to remain silent, merely holding the exhausted prince and rubbing his back and thighs. They found out very quickly that Levi's legs were very sensitive, so Eren made sure to use that to his advantage when they were doing naughty things. But they were also very soothing to the raven, so Eren would often massage them when they sat together.

"Did you meet with the prince of Utgard?" Eren eventually asked, whispering the question in case Levi had fallen asleep. He immediately received a snort and a story. It got more and more ridiculous as Levi explained how the prince had obviously not gotten out much and had horrible manners. "And then the idiot starts flirting with my mother. Eren don't laugh I'm still traumatized. She handled it with grace and poise, as always, but as soon as he was gone I got an earful. But now we maintain good relations with them so we won't have to see them until our grandchildren are older." Levi murmured, eyes drooping with exhaustion. He fought the heady call of slumber, wanting to spend more time with his mate before he leaves again. At the mention of children, he smiled, remembering why he was so excited for Levi to come home.

"Levi." He called, getting only a grumble in return. Eren nudged his thigh and nuzzled his hair. "Levi~" He called again, finally getting the tired mer to look at him. Eren thumbed at the dark marks beneath his mates eyes, sad to see he hadn't been sleeping back at the palace. Levi had once confided that without Eren, he found sleep nearly impossible. Apparently while at the palace he sleeps for only a few hours. _Guess we can skip the movie and go straight to bed._

"What?" He grumbled, the relaxation of being with Eren demanding his tired body rest.

"I have big news." Eren sang, hoping to get Levi excited. It seemed to work, his eyes widening from a barely there squint to his usual glare.

"Big news? What big news?"

"Guess." Eren was nearly vibrating with excitement, the movement enough to jostle the male on his lap to sit up a bit more. Levi was waking up a bit more, definitely curious as to what could cause such a reaction in his mate.

"Nn… you took a good shit?" He guessed, enjoying the small shove to his shoulder as Eren shook his head and laughed. Levi loved Eren's laugh. Well, really he loved his voice. And his hair. And his eyes. And his mouth. And his-

_"Levi!" _Eren whined. _Oh right, I'm supposed to be guessing._

"Uh, you fixed the toilet? You… uh… Did you eat something really good? Oh! You got a-a whatthefuckisitcalled proabortion?"

"Promotion?"

"Yeah, that."

Eren sighed. "No, I didn't get a promotion sadly."

"Give me a hint then," Levi whined, shoving his face in Eren's neck and just breathing in his scent. Eren laughed but obliged.

"When you brought me to the cave for the first time, you wanted this. It was something you promised you would give me." Eren explained, waiting for the metaphorical light bulb to flick on._ C'mon Levi._ Levi remained slumped, trying to think of anything he had promised and had yet to deliver.

"I… a house? Food? Comfort? Love? You know I love you more than… well, anything. To be by your side?" Levi guessed but Eren shook his head.

"What is it?" Levi finally asked, tired and hungry and just wanting to be with Eren, he really couldn't figure out what it was.

"Levi." Eren murmured, kissing him softly as soon as Levi looked up. Levi accepted the kiss happily, succumbing to the addictive magic that was his lips while Eren whispered the words 'I love you' over and over again. Eren pulled back, eyes large and dewy, the beautiful green color Levi desperately loved filled with joy._ What-_

"I'm pregnant."

Two words. Levi never expected two words to completely freeze time, his heart pumping like he swam from Jinae to Karanes in one go. _Eren… is carrying… my pups? He's… pregnant._ His heart was beating too fast, the smile spreading his lips hurt, and the water trailing down his cheeks weren't from his damp hair. "Pregnant?" He asked, a mere whisper off his lips as Eren nodded, wiping his own tears with a small laugh.

"I found out yesterday. Hanji came by while I was feeling sick and asked to do a test. She found out I was pregnant. Levi, we're gonna be parents." Eren explained, wiping tears from Levi's eyes and kissing his nose. Levi was in shock. Hanji had told him that half mer breedings were rare, only 5 have ever been recorded in all of history. Levi had hoped, he really did since Hani had said that 3 of the 5 had royal blood and since Eren did as well he might be capable, but Levi had already accepted that it would probably just be him and Eren, which he was more than ok with._ We're having pups._

"We're having pups." Levi repeated, Eren nodding as Levi finally began to move, arms crushing Eren to his lips as he repeated the mantra over and over. Somehow in the ordeal of happy squeals and laughter, Eren was lying down on the couch with Levi on top of him. Clothes began to disappear, and soon Levi was fully hilted inside him, murmuring incoherently about 'making more while we're at it.' After the two finally reached orgasm, they cuddled happily, lips locked as they felt one another, Levi cradling the stomach that was currently housing his dick, his fresh batch of seed, and his little pups. _Pups. We're having pups._ Levi's face hurt from all the smiling, but he was too happy to care.

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**hey so he's pregnant! Anyone got any predictions for next chapter?**


	6. What kind of Disney Shit is this?

**Last Time on Aquarium: Eren and Levi share domestic bliss, Eren being happy to see Levi after he was gone for a few days. Jean showed up, stupid Jean, but Levi told him to fuck off with mer powers. Eren then revealed he was with child, much to Levi's excitement.**

**This Time on Aquarium: Eren's pregnancy, life with the kids, and more unexpected guests that Eren might not be able to handle**

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**This is it. The final chapter. It feels great, but I'm sad. I really had to stop myself from adding anymore lol. This was supposed to be 2 chapters. 2! ah... it's sad. I want to keep writing, and yet this feels like a good place to stop. I'm gonna start working on my other stories that have yet to be finished so please read them as well! I hope you enjoy the final chapter of Aquarium!**

**Also, please consider visiting hPKJrwQfk and donating $3 to my broke college ass. Or just look at it to make me feel better lol. Enjoy reading!**

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The pregnancy had its ups and downs.

Levi began to stay home longer and more frequently. He got shit for it at first, from many different people really coming to land to request his ideas, but Levi out an end to it immediately, threatening to renounce his crown if he couldn't spend more alone time with his pregnant mate. They backed off quickly. Eren had a great time now that Levi stayed home. Every morning he'd wake up to food and cuddles and a very excited Levi. He thought that because of the pregnancy, their sex life would take a dip since he figured Levi slept with him to sate his desire to breed.

Oh boi was he wrong. If anything it only increased their dirty fun. Apparently, Levi could smell the fact that he was pregnant, and that got him going like nothing else. Eren wouldn't even be doing anything arousing, and all of a sudden Levi was on him, taking him in the kitchen, the den, the basement, hell one time he took him in the garden. The mer prince became insatiable when Eren was involved, not that Eren was complaining. He honestly loved all the attention, all the little notes Levi would write and hide around the house so that when he was gone, Eren would feel less lonely.

It started getting weird when his stomach began to grow. It was an odd feeling, and he kept getting sick in the mornings. He also would feel pain in his pelvis and on his perineum sometimes but it only ever lasted a few moments so he didn't worry too much. He especially didn't tell Levi. Levi got worried and protective over anything he saw as a threat. One time while Eren was watering the flower bed with Levi, a neighbor with her dog walked down the street and the dog barked at them. You'd think the dog had been foaming at the mouth and jumping the fence by the way Levi reacted. He was growling, the sky darkening with the storm clouds and his form began to revert back to a merman with long deadly claws. Thankfully the woman hadn't noticed his husband, but the little dachshund sure did, immediately whimpering and trying to hide behind his owner. Levi got quite the talk once Eren managed to drag him inside. Not that Levi was truly listening, more focused on Eren's kiss-swollen lips and his protruding stomach.

Hanji came nearly every week to check on him, conducting tests to see how the 'little guppikins' are. Levi wanted to be there every time she was, to ensure she didn't do something but she often figured out when he was gone. At 6 months, Eren looked like he swallowed a pumpkin. Everything felt like too much effort, and he had the weirdest cravings for Mexican food. Eren had quit his job months ago, not wanting anyone to know he was pregnant since it wasn't exactly normal for males to be pregnant. Eren was really worried at first since he was the only one making money so how the fuck were they gonna pay the bills? Turns out, Levi's good for that too. When Levi offered to pay, Eren had laughed, because any sort of currency they use would definitely be different, but turns out Levi had something else in mind. Levi knew where quite a bit of shipwrecks were and he was able to loot them. When he suddenly walked out of the sea with a whole ass chest of jewelry and old ceramic vases, Eren knew he had nothing to worry about. Levi had been very happy to hear that.

At 7 months, Eren felt a lot of pain in his pelvic area. It was to the point that he had to tell Levi, who was quick to scoop him up and bring him to the cave. Much to their surprise, Hanji told them that he was having contractions and that it was time to give birth. There was concern on both sides since mers had a 9 to 10 month gestation period, and humans had 9. 7 wasn't in range of either. Hanji monitored him closely, assuring him that she found no signs of ailing health in either what they assumed was 1 or 2 pups, or in him. He went into labor a half an hour later, his mom, Kuchel, Kenny, and Hanji were all crowded about their cave, offering support as Eren cried at the horrible pain. He kept apologizing to his mom, for putting her through the same thing at some point. She laughed then, telling him it was worth it when she got to hold him for the first time. Eren could only hope it would end soon. Levi was in his original form, Eren's back pressed to his chest as he hugged him from behind, keeping up a steady croon to try and soothe him while his tail wrapped around his leg. Levi was quite honestly scared shitless. They still hadn't come up with names, still had no idea if the pup would be able to live underwater. Hanji had Eren's hips in the shallow end, allowing the pups to 'swim' out of the womb as a regular mer would.

After about 20 minutes, Eren gave birth to the first pup. Just as Hanji said, the little thing swam, in a blur of blood it breached the surface where Hanji gently scooped it up to check for anything wrong. Hanji quickly announced that it was, in fact, a she and that _she_ was quite feisty. She was tiny, no larger than Levi's hand and crying out with little squeaks and clicks. She had a tail, but the translucent flesh showed the human legs underneath. Her eyes were open and looking about wildly as Hanji handed her to Eren. His mom had been right, holding the tiny creature was most definitely worth the pain. She eventually found Eren's nipple, digging into the feast she had been crying for. Eren held her there and cried, turning his head to kiss Levi's cheek and nuzzled into him. Levi couldn't look away from the pup, completely and utterly taken by the tiny thing. The pups kept coming after that, small bodies all with translucent tails showing off human legs sliding into the world with small chirps and clicks. After 2 hours, Eren gave birth to 6 pups. Levi felt overwhelmed with love and joy, having only expected one or maybe two since mers only ever birthed one.

Eren weakly smiled at Levi completely melting his heart when he leaned back against him and sighed. "We did it." Eren murmured, Levi corralling the chittering pups onto Eren chest so that they could rest. "You did it, love. I'm so proud of you. They're so perfect. Look how happy they are. You did such a good job." Levi praised, hands touching and rubbing at Eren's sides and chest. Hanji did a thorough look over of all the pups, each one whining to be let go and put back on their mama's stomach. Levi watched each one like a shark, unwilling to allow them out of his sight as Eren fell in and out of sleep. She gave them a clean bill of health and ushered the proud moms and traumatized uncle out to give the new parents some time with their new additions. Levi kept vigilant guard of the pups while Eren slept.

After a good nap, Eren woke up to find the pups in the water. Eren panicked at first, but then saw that Levi was in their as well, two of the pups hitching a ride on Levi's hair and hand. Turns out they were inclined to both water and land. After their nap with mama, they had immediately slipped into the water, swimming about happily. Unlike Eren, they seemed to filter oxygen through their gills like a mer, meaning that they could live underwater. Levi had been worried that they wouldn't be able to switch, as most pups had a hard time learning to go from water to air, but they were naturals. They clicked at their dad underwater and made vowel sounds at him above. Levi was in awe at the cute little things. Kuchel and Carla eventually came back, absolutely delighted at the sight of the swimming pups who swam up and chirped at them. Eren was grateful that they all seemed healthy, still very much feeling exhausted from the pain he had experienced only a little while earlier.

The pups made sure to give him attention too. After swimming about their father, they would crawl up Eren's legs and lay on his chest, one more adventurous pup climbing onto his face to lay on his nose while the others stopped at his neck. After a few days, Eren felt well enough to play with them in the water, Levi twirling him about happily while the pups clung to them. They were growing fast, about an inch or two longer and their tails a little darker in hue. Their vocalizations were becoming more complex, whistles and growls becoming apart of their vocabulary while Eren helped them learn more human vocals. He attempted to teach them their names, but they merely chirped in recognition. Carla and Kuchel have been dealing with the kingdoms who quickly learned of the new royals. Apparently, the politics behind naming was important so Levi and Eren made an agreement. All the boys would follow the traditional names of Shiganshina, while the girls would follow the naming traditions of Trost. They were both presented the prospective names and chose, finding that the whole ordeal was actually quite nice. After another week, Eren felt well enough to travel with the pups and they paid a visit to the palace. Eren was quite surprised to see such a large gathering of mers, all congratulating him and Levi while praising the pups. All the pups clung to Eren in some way, from his hair, hands, arms, ears and clothing. They were curious and wanted to explore, but Levi's protective presence behind Eren watched their every move to ensure no harm could come to them. The king of Shiganshina even came, hugging his daughter and meeting his grandson and grandchildren. It was a joyous experience, and Eren was glad everything turned out alright.

**[Aquarium]**

**[1 year later]**

"Woah, he must be earning good money," Armin remarked as they finally parked in the driveway. The house looked brand new with a flourishing flower bed out front and a cute walkway leading to the front door. Armin and Mikasa had been worried about Eren for the last few years but didn't have the money to come back to America nor the time to visit. They called him often, but until last year he didn't sound like his usual happy self. When he had admitted that he had gotten a boyfriend, Armin was ecstatic for him while Mikasa had been very protective as usual. It wasn't until now that they would finally be meeting this mysterious Levi in person.

"Are you sure we shouldn't have called him first?" Mikasa asked as she parked the car, the two unbuckling and stepping out the car.

"It's a surprise! He'll be so excited to see us that he won't even care." Armin cheered, pulling Mikasa along to the door while vibrating in excitement.

"I guess that's true. It's been almost 2 years since we last saw him." Mikasa agreed, knocking on the front door and pulling up her red scarf. They waited a few moments before the sound of running could be heard and the door cracked open. Where they expected to see Eren, they saw a little girl instead. She had long black hair and cute little bangs, tan skin and a light blue swimsuit with a skirt on. What caught their attention was her eyes, she had Eren's eyes. "Hello?" She greeted, holding the door wider to really look at the two. The two friends looked at one another in confusion. _Maybe he's babysitting?_

"Ah, hello there! Is Eren home?" Armin asked politely, bending down a bit to be more level with the little girl. Shamira tilted her head as she thought about the noise, realizing it was what daddy sometimes called mama. She clicked an affirmation, turning a bit when she felt Hakan grabbing her back shyly. She whistled out the question and he chirped back, looking at the two strangers with familiarity. _' I recognize them.'_ He whistled to her, ignoring the confusion on their faces as they heard mama starting to stand, no doubt wondering where they went without the rest of their sandwich.

"Mama!" Shamira called, just to make sure he was actually coming. She studied the strangers and realized that she too recognized them. "Who are you?" She asked, head tilting adorably as Hakan slowly inched forward, his brown skirt and blue shirt wrinkling as he hesitantly bunched them together.

"I'm Armin and this is Mikasa. Mikasa is his sister and I'm his friend. What's your name?" Armin introduced, hearing peels of laughter just inside. _More children. Is that how he made the money? Babysitting? Why did she call for her mother?_ "I'm Shamira and this is Hakan. Say hi, Haka." Shamira pushed the shy boy forward. Unlike his sister, he had silver eyes and fairer skin, but they shared the same black hair. He chirped a greeting, earning a pinch from his older sister. "They don't understand that! Human speak Haka!" She reminded and he nodded, rubbing his arm where she pinched him. "H-hi."

Eren walked around the corner then, his instincts telling him that Mira wouldn't just run towards the door and abandon her PB&J for no reason. He wasn't expecting to see that Shamira had answered the door, and his sister and best friend were standing right outside of it. "Mama!" Hakan immediately cheered, running away from the strangers to instead demand that mama carry him. Eren did so without a second thought, used to his mama's boy clinging to him wherever he went.

"Armin, Mikasa! What are you guys doing here!?" Eren cheered, quickly giving the two a hug with Hakan on his hip. The two were still confused but were glad to see Eren. He looked a lot healthier and happier than they've ever seen him, and clearly, these kids loved him. He wore a plain white shirt with a few purple stains on it and black swim shorts. His hair was long and tied in a messy bun at the base of his neck, eyes glittering as he looked at his longtime friend and sister. "We wanted to see you. It's been 2 years since my last visit." Mikasa explained, a small smile pulling her usually stoic lips as she studied her brother. "Yeah! It's been 3 for me! I've missed you!" Armin cheered, calming when he saw how the little boy hid in Eren's neck. "Ah, sorry if we caught you at a bad time. Are you babysitting?" Armin asked, coming inside when Eren ushered the two forward and Shamira shut the door behind them. Eren froze, suddenly realizing that he's gonna have to explain all this to his best friends._ Fuck._

"Um, not exactly…" Eren murmured. He put down his squirming son and ushered him and Shamira down the hall. "Go eat your sandwiches," Eren told them, watching as they giggled and trotted down the hall, bumping into Levi as he turned the corner. "Oi! No running you'll trip!" He barked, the two slowing but still excited to eat. Levi sighed but saw the two strangers and immediately got defensive, coming forward to protectively wrap an arm around Eren's waist. He was also wearing a black skirt and nothing else, showing off his 8 pack and strong legs. He also felt their faces were familiar, but couldn't place it.

"Levi, um, this is my sister Mikasa, and my best friend Armin. They dropped by for a surprise visit." Eren explained, eyeing his mate and his defensive posture. Mikasa looked defensive as well, eyeing Levi's arm on his waist and balling her hands. It was the acute observance that had her realizing that both he and Eren wore rings. "Eren… are you…" She started, shock on her features as she stared at them. Armin looked over at her questioningly, but soon saw what she was looking at.

"Holy smokes… Eren, you're married. Wait! Are those kids… yours?! You adopted!?" Armin fired off, the realizations hitting him while Eren groaned and bent down to hide his face in Levi's hair. "Not exactly. Damn, why do you have to be so smart." Eren complained, Levi patting his back and studying the two._ That's why I recognize them._ Eren had quite a few photos with them scattered about the house. "Eren, you got married and didn't even tell us? We weren't even invited to the wedding…" Mikasa started, but Eren was shaking his head. "Look, it's more complicated than it seems. Levi, can you go watch the kids while I talk to them?" Eren asked sweetly, Levi leaning up to kiss his cheek before turning around to go sit with his pups while they ate. Once alone, Eren showed them the living room, sitting on one of the couches while they sat across from him.

"I… I really don't know how to explain this. So much has happened since I last saw you." Eren started, rubbing the back of his neck. The two just stared, hurt written across their faces. "How about starting with… Levi was it? How long have you been married? When did you meet?" Armin hedged, clearly curious but angry that he wasn't aware of such big news. _Whatever the reason is, it better be good._

"Ok, well I met Levi only a few months after Mikasa's last visit so I'd say… a year and 9 months? Um… we've been officially married according to state law for about a year and 6 months. We had to wait to get the necessary paperwork for Levi to be a citizen first. But we kind of maybe… married the first day we met." Eren explained slowly, trying hard to find the words to explain such a bizarre situation. The two were gaping at him. "You married someone you just met?! What is this a Disney movie!?" Mikasa yelled, standing with the force of her emotion. The loud noise was enough for Levi to be immediately by his side, Aytac following his dad and staring at the two strangers in confusion. Aytac looked back and forth between the bickering adults with curious silver eyes, pushing his long brown hair back every time it fell into his pale face.

"Mikasa calm down! I know it sounds horribly quick and irrational, but it was kind of fate. Um, Levi? Can you… show them?" Eren quickly asked, realizing now that he can explain all he wants, but they wouldn't believe or understand if they didn't see first hand what Levi was. Levi nodded, understanding what Eren wanted and sat down beside him. He willed the stretch, the change and quickly felt his tail begin to take form. His fangs elongating and his fins slowly opening. The two looked on in shock while Aytac merely cheered, clicking to his siblings that daddy was ready to swim. Soon Levi was fully transformed, and all 6 of the kids were running in, bouncing up and down in excitement for more swimming. "Um so yeah Levi is a merman and I'm also a half mer and that's how this all happened the end." Eren quickly spat out, hoping that would be all the explaining necessary. He was wrong.

"Eren what the hell!? What do you mean your half? What just happened. Levi is… is…" Armin tried, his more logical mind trying to think of rational justifications but coming up short.

"Daddy's a merman!" Nava cheered, running up to him and grabbing his hand. "Are we swimming now daddy?" She asked hopeful, the little Eren look-alike with her long brown hair, tan skin, and blue-green eyes that made Levi's heart melt. "Did you finish your lunch?" He asked, already knowing that by her falling expression she did not. "No." She admitted, always so honest.

"Then go take your siblings back to the den to finish. Once you are all done we'll go swimming." Levi ordered, nuzzling her hair and petting her arm.

"Ok daddy!" Nava cheered, running up to Emirhan to pull her whining older brother along while the others followed quickly behind them. Emirhan gave one last look at the strangers, black bangs shadowing the curious gold eyes as he was unwilling pulled by his sister. _Go figures. I always miss the action._

The three had watched the cute interaction before all attention once again shifted to Levi and his tail. With a sigh, Eren tried to recount the tale that lead them there (Minus all the fucking) and how they were mated. Armin only interrupted to ask questions, in which Eren tried his best to explain. Levi just sat prettily beside Eren, content to just be near him as he explained. Mikasa had hidden most of her face behind her scarf, so it was a little hard to tell how she felt. The kids suddenly began cheering in the other room, Eren and Levi looking at one another as mixed chirps and cries of 'Nana' and 'Nuna' were heard. _Oh fuck._ They heard Carla chirping back at the excitable kids, asking them where their parents were. Mikasa and Armin both heard and recognized the voice, eyes widening in shock as the kids lead there Nana and Nuna to them. Kuchel and Carla wore wet shirts and skirts, Carla's eyes widening in shock at seeing Armin and Mikasa.

"Mrs. Jaeger!?" Armin squeaked, eyes running with tears as Mikasa tore pass him to hug her. Carla was shocked but nonetheless hugged her adoptive daughter, happy to see her after such time. Kuchel just looked on in curiosity, not entirely sure what was happening but sure that her son would fill her in.

"Hi guys… I'm assuming that Eren was in the middle of explaining… all of this." Carla asked after a minute of hugging. The two nodded and she sighed. "Did I come in too early?" More nodding. She sighed and motioned for Armin, who was quick to get up and hug her as well. The next 20 minutes was Carla explaining her 'death' and the events leading up to it. Levi had shifted back to get the kids under control and to explain to his own mother what the fuck was going on, to which she just laughed. "Sounds like you guys have your hands full. Want me to take the pups?" She asked, to which Levi agreed.

Kuchel clicked at the kids, who immediately turned to look at their Nuna. "Who wants to go swimming with Nuna?" As soon as the word swim left her lips, the pups were in a frenzy of cries and squeals, jumping up and down with Atarah and Aytac already running to the glass door that leads to the backyard. Levi was grateful to the two mothers, they often came to visit and loved to play with the kids. In those moments, the new parents got a break to cuddle one another and do more… inappropriate things.

"So… you've married a merman, found out your mom's not dead and found out you are the royal prince of a mermaid society because you are also a merman? Am I getting this right?" Armin asked Eren, who Levi went to go sit with again. Eren laughed at the summary, but nodded, leaning into Levi and holding his hand as soon as he was close.

"Yeah, not bad eh?" Eren joked, earning a chuckle from Armin and Carla.

"What about the kids?" Mikasa asked, breaking her silence as she looked at the happy couple. She didn't feel as defensive anymore, knowing that Carla would never allow her brother to marry someone he didn't love and who didn't take care of him. From what she could see, Levi would offer his support whenever Eren wanted it. The question caused the 3 mers to look at one another, knowing that this would be almost as unbelievable as the rest of the story.

"Well… they're ours. It turns out that I… uh… can become pregnant. Weird mermaid shit I don't understand but I gave birth a few months after we married." Eren explained, looking at the mers for confirmation who both nodded. "Wait, but that means those kids are only a year old! They look about 4 or 5 years old?!" Armin quickly interjected, seemingly unperturbed that Eren gave birth.

"Uh, yeah turns out mers grow at a different pace. The whole situation was wack if you ask me. I get pregnant, carry them for 7 months and give birth to 6 little things. Oh, you should have seen them. They were no bigger than my hand with translucent tails and cute little faces. They're so smart Armin. They were swimming around and chirping at us hours after they were born. We were all really surprised, they don't look like human or merbabies, and I gave birth to 6 of them. Mers only give birth to one and sometimes two. The whole situation was just… wack." Eren explained, pulling out his phone and scrolling through his phone until he found what he was looking for. Most of them were of Levi, whether it be sleeping, eating, cuddling, Eren saved them all. He showed them Levi cuddling up to his stomach, head resting there as he sang to what they thought was one or two pups. Pictures he took when he came home after giving birth, the pups being about the size of his arm and wobbling around on little human legs. They stayed there looking at photos until a small tanned hand reached up and grabbed Eren's arm. Atarah stood there, dripping wet and looking at her mama with beautiful forest green eyes.

"Um… can mama and papa come swim with us?" Atarah murmured, feeling a bit shy in front of two strangers but her want for her parents was stronger than her fear. Eren cooed, handing Mikasa his phone while he pulled his little girl into his lap. "How about, Mama and Papa will come swim if you ask Aunt Mikasa and Uncle Armin if they want to swim as well? You know, they've never seen a mermaid swim." Eren offered, noting how she looked at Armin after she heard the word uncle. The only uncle they know is Kenny, who was also like a grandpa to them. She gasped, obviously surprised. "Really!? Do they not have tails like Mama?" She whispered like any child would, loud enough that anyone listening could clearly hear. Eren nodded, tucking a strand of her beautiful brown hair behind her ear.

"That's right sweetie. They're only human." Eren explained and smiled when she nodded with understanding. She turned to look at Mikasa, quickly sliding off Eren's lap and standing in front of her. "Auntie Mikasa? Can you come swim with me? I want to show you how a mermaid swims!" She asked sweetly, a small smile pulling at Mikasa's lips at the cute display. She nodded, and Atarah quickly walked over to Armin. "You too, Uncle Armin? I have a new trick, where I do a spin and then a fwoosh but I come down and and and do another spin!" Atarah explained, making hand movements to show her uncle just how cool her trick was. Armin accepted happily, and the little family went outside, ready to see Atarah's new trick.

**[Aquarium]**

**[3 Years Later]**

Eren never thought he could be happier than he was now. All his kids were running around the beach with Aunt Mikasa and Uncle Armin, shooting them with water soakers while Eren and Levi made lunch and watched through the little window above the sink. Well, if by making lunch he meant currently being stuffed full with Levi's tongue then sure making lunch works. Levi thought it a good idea to forget about the fries currently burning in the oven to instead eat out his mate now that the kids were preoccupied with something else.

"Agh… Levi…! What if they come in!" Eren hissed, gripping the sink and attempting to watch the kids dunk their unsuspecting uncle into a really large puddle they made with their newly appearing magic powers. Levi's tongue pushed forward suddenly, Eren holding in a scream at the sudden pleasure that shot through him. _Oh fuck. I'm close._ Levi was thorough, moaning at the taste of his mate as his tongue masterfully fucked him into an orgasm. Eren bit down hard onto the side of his hand to silence his cries, worried that despite being far, his kids scarily acute hearing would pick it up. With a few last licks, Levi pulled back with a smirk and patted Eren's ass, enjoying the bounce and squeal he got in return. With quick movements, he pulled up his mates underwear and pants before pulling out the black fries. Eren stood there, dazed and panting as he tried to remember what it was he was supposed to be doing. That is until he realized that he, unfortunately, came all over the counter.

"Dammit Levi!" He growled, getting a wet cloth to wipe up the mess. Levi just snickered, watching his love clean with a fond look. "So, my mom is coming later to pick up the kids." Levi began, leaning against the counter and popping a fry in his mouth. _Ew, fucking burnt._ He quickly spits out the offending fry and dumped the whole tray, chuckling when he felt Eren's glare. "Oh? Is that so?" He asked, still glaring at the raven before turning back to the chicken tenders for the kids. Levi hummed, definitely not staring at Eren's plump ass, licking his lips where he pleasantly found more of Eren's flavor.

"And what exactly is she picking them up for?" Eren asked, slamming the ketchup bottle against the counter like it owed him money.

"Well," Levi started as soon as Eren managed to get some ketchup out, smiling at the cute smiley faces he was drawing on the kid's plates. "I'm taking you on a date. Just you and me." Levi purred, coming up behind the smiling brunet and hugging him, resting his cheek on Eren's muscled shoulder blades. "Oh really? What's the special occasion?" Eren asked, plating the tenders before turning to see his husband. Levi hummed, looking up at his brat with a fondness that always took Eren's breath away.

"Tonight's the Blue Moon. We've been mated for 5 years." Levi murmured, reaching up to peck Eren's lips. "Also," He added, silver eyes glittering with mischief as he leaned forward to whisper in Eren's ear. "I plan on fucking you full of my next litter." He teased, noting the little moan Eren let out.

_"Levi…"_ Eren whined, reaching back to grip the counter. Levi chuckled and slapped his ass before quickly walking to the glass doors. "Later love. Be a good boy and maybe I'll give you a reward." He ordered, eyes dark for a moment as he looked at his squirming husband. _So beautiful._ His attention was quickly stolen by Shamira, calling out for him to help rescue Armin from her rambunctious younger siblings. Eren watched him go with a whimper, mentally preparing himself for the boner he'll keep until tonight.

Days like these were all he needed. The aquarium he had been trapped in, lonely and scared, was broken. A heart-shaped hole pouring him into the arms of his love and his beautiful children, all smiling and happy.

There was truly nothing more he could ask for.

* * *

**Thank you so much for reading, I hope you enjoyed this as much as I did! Anything surprise y'all? Anything you wanted to see?**

**Also, please support my dumb ass and buy me a $3 coffee. Cause you love me. Right?**

** hPKJrwQfk**

**So I tried to give brief descriptions of the kids but here is a list in case y'all were interested in my naming process.**

**(Listed in order of oldest to youngest)**

Shamira - Black hair, Eren's eyes, tan  
SHAMIRA שָׁמִירָה - Means "guardian, protector" in Hebrew.

Emirhan - Black hair, Gold eyes, tan  
EMİRHAN  
Derived from Turkish emir "amir, prince" and han "khan, ruler, leader".

Aytac - Brown hair, Levi's eyes, pale  
AYTAÇ  
Derived from Turkish ay meaning "moon" and taç meaning "crown"

Atarah - Brown hair, Green eyes, tan  
ATARAH עֲטָרָה  
Means "crown" in Hebrew

Hakan - Black hair, Levi's eyes, pale  
HAKAN  
Means Emperor, Ruler in Turkish

Nava - Brown hair, Eren's eyes, tan  
NAVA נָאוָה f Hebrew  
Means "beautiful" in Hebrew.


End file.
